Laws
State and federal legislation related to book bans, library restrictions, and educational content restrictions. Every law is tracked with a full legislative timeline and linked sources.
Alabama
Alaska
Arizona
SB 1435
AdvancedThe bill has passed one chamber (House or Senate) and moved to the other.Schools; libraries; explicit materials; training
Passed Feb 2026
HB 2008
FailedThe bill did not pass — it was voted down or expired without action.School libraries; professional associations; prohibitions
Passed Feb 2026
Arkansas
California
AB 1078
SignedThe governor has signed the bill into law.Instructional materials and curriculum: diversity.
Passed May 2023
AB 1185
FailedThe bill did not pass — it was voted down or expired without action.California Library Services, Equity in Opportunity Act.
SB 478
FailedThe bill did not pass — it was voted down or expired without action.School accountability: Statewide School Library Lead.
Colorado
Delaware
Florida
H 1119
FailedThe bill did not pass — it was voted down or expired without action.Materials Harmful to Minors
Passed Feb 2026
H 1069
Struck DownA court has ruled this law unconstitutional — it cannot be enforced.Education
Passed Mar 2023729 linked books
H 1557
SignedThe governor has signed the bill into law.Parental Rights in Education
Passed Feb 2022
H 1467
SignedThe governor has signed the bill into law.K-12 Education
Passed Feb 2022729 linked books
S 1692
FailedThe bill did not pass — it was voted down or expired without action.Materials Harmful to Minors
HB1071
FailedThe bill did not pass — it was voted down or expired without action.Education
SB1106
FailedThe bill did not pass — it was voted down or expired without action.Recognizing Judea and Samaria
HB31
FailedThe bill did not pass — it was voted down or expired without action.Recognizing Judea and Samaria
Georgia
SB 74
AdvancedThe bill has passed one chamber (House or Senate) and moved to the other.Harmful Materials to Minors; exemption for libraries and librarians from the provisions of Code Section 16-12-103; repeal
Passed Mar 2025
SB 226
SignedThe governor has signed the bill into law.Sale or Distribution of Harmful Materials to Minors; provisions of Code Section 16-12-103 shall be applicable to libraries operated by schools; provide
Passed Mar 2021
SB 248
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Georgia Council on Library Materials Standards; establish and provide
Hawaii
Idaho
S 1448
SignedThe governor has signed the bill into law.Amends existing law to revise provisions regarding material harmful to minors.
Passed Apr 2026
H 0710
SignedThe governor has signed the bill into law.Amends and adds to existing law to prohibit certain materials from being promoted, given, or made available to a minor by a school or public library, to provide for a cause of action, to provide for damages, and to provide for injunctive relief.
Passed Mar 2024
H 0819
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Amends existing law to revise provisions regarding material harmful to minors.
H 0796
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Amends existing law to revise provisions regarding material harmful to minors.
Illinois
HB 5236
AdvancedThe bill has passed one chamber (House or Senate) and moved to the other.DIGITAL LIBRARY PROTECTION ACT
Passed Apr 2026
HB 2789
SignedThe governor has signed the bill into law.LIBRARY SYSTEMS-BOOK BANNING
Passed Mar 2023
HB 5279
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.DIGITAL LIBRARY PROTECTION ACT
HB 4241
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.SCH BOOK RATING & TRANSPARENCY
Indiana
Iowa
SF 496
UpheldA court has ruled that this law is constitutional and may be enforced.A bill for an act relating to children and students, including establishing a parent's or guardian's right to make decisions affecting the parent's or guardian's child, authorizing the parent or guardian of a student enrolled in a school district to enroll the student in another attendance center within the same school district in certain specified circumstances, prohibiting instruction related to gender identity and sexual orientation in school districts, charter schools, and innovation zone schools in kindergarten through grade six, and modifying provisions related to student health screenings, school district library programs, the educational program provided to students enrolled in school districts, accredited nonpublic schools, and charter schools, other duties of school districts, accredited nonpublic schools, the department of education, the board of educational examiners, and the governing boards of charter schools and innovation zone schools, competent private instruction, and special education, and including effective date provisions. (Formerly SSB 1145.) Effective date: 05/26/2023, 07/01/2023.
Passed Mar 202319 linked books
HF 2622
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.A bill for an act relating to public libraries, including eligibility requirements for state assistance and oversight by city councils.(Formerly HSB 720.)
HSB 720
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.A bill for an act relating to public libraries, including eligibility requirements for state assistance and oversight by city councils.(See HF 2622.)
HF 2309
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.A bill for an act relating to public library requirements for materials harmful to minors, and providing civil and criminal penalties, and including effective date and applicability provisions.
SF 2177
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.A bill for an act relating to policies and protection measures a library provider or third party contracting with a library provider must take if the library provider or third party offers digital library services.
SF 2119
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.A bill for an act relating to obscenity exemptions for public libraries and educational institutions.
HF 558
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.A bill for an act prohibiting certain materials in public libraries in counties and cities, authorizing civil actions, and providing civil penalties.
HF 554
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.A bill for an act relating to public schools, including by modifying provisions related to school district library programs and requests to remove educational materials from classrooms and school libraries.
HF 521
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.A bill for an act relating to obscenity exemptions for public libraries and educational institutions.(Formerly HF 274.)
SF 347
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.A bill for an act prohibiting certain materials in public libraries in counties and cities, authorizing civil actions, and providing civil penalties.
SF 235
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.A bill for an act relating to obscenity exemptions for public libraries and educational institutions.
HF 274
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.A bill for an act relating to obscenity exemptions for public libraries and educational institutions.(See HF 521.)
SF 181
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.A bill for an act establishing requirements related to electronic resources provided by postsecondary schools, public libraries, schools, and state agencies to students enrolled in kindergarten through grade twelve, providing penalties, and including effective date provisions.
SF 113
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.A bill for an act relating to children and students, including by modifying provisions related to a parent's or guardian's rights to make decisions affecting the parent's or guardian's child, the educational program and human growth and development curriculum provided to students enrolled in school districts, charter schools, and innovation zone schools, student health screenings, school district library programs, special education, and other duties of school districts and the governing boards of charter schools and innovation zone schools.
Kentucky
Louisiana
Maryland
Massachusetts
S 2710
AdvancedThe bill has passed one chamber (House or Senate) and moved to the other.Addressing challenges facing public libraries and digital resource collections
Passed Nov 2025
S 2330
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Addressing challenges facing public libraries and digital resource collections
H 3598
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Protecting against attempts to ban, remove, or restrict library access to materials
H 3595
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Addressing challenges facing public libraries and digital resource collections
Michigan
HB 4250
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Libraries: policies and practices; public library freedom to read act; establish. Creates new act. TIE BAR WITH: HB 4251'25
HB 4251
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Libraries: policies and practices; district library freedom to read act; establish. Creates new act. TIE BAR WITH: HB 4250'25
Minnesota
SF 3567
SignedThe governor has signed the bill into law.Omnibus Education policy bill
Passed Apr 2024
HF 564
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Certain material prohibited in school libraries.
HF 3698
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Certain terms in libraries' electronic book and digital audiobook license agreements or contracts prohibited.
SF 3685
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Certain libraries' electronic book and digital audiobook license agreements or contracts terms prohibition
SF 797
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.School libraries certain material prohibition provision
Mississippi
SB 2346
SignedThe governor has signed the bill into law.Material harmful to minors; provide for liability for any entity that distributes on the internet without age verification.
Passed Feb 20234 linked books
HB 1315
SignedThe governor has signed the bill into law.Pornographic online and digital/resources for K-12 students; prohibit.
Passed Feb 20234 linked books
SB 2812
FailedThe bill did not pass — it was voted down or expired without action.Crime of distribution of obscene materials; delete exemption for public and private school libraries.
Missouri
SB 775
SignedThe governor has signed the bill into law.Modifies provisions relating to judicial proceedings
Passed Mar 2022
SB 1136
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Establishes provisions relating to the reconsideration of materials in a public library or public school library
Montana
Nebraska
LB 390
SignedThe governor has signed the bill into law.Require each school board to adopt a policy relating to access by a parent, guardian, or educational decisionmaker to certain school library information
Passed Apr 2025
LB 441
FailedThe bill did not pass — it was voted down or expired without action.Change provisions relating to obscenity
New Hampshire
SB 208
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Requiring local school boards and public libraries to adopt curation policies.
HB 324
FailedThe bill did not pass — it was voted down or expired without action.Relative to prohibiting obscene or harmful sexual materials in schools.
New Jersey
A 2312
AdvancedThe bill has passed one chamber (House or Senate) and moved to the other.Creates separate crime for items depicting sexual exploitation or abuse of children; concerns computer generated or manipulated sexually explicit images.
Passed Mar 2026
A3446
SignedThe governor has signed the bill into law."Freedom to Read Act"; establishes requirements for library material in public school libraries and public libraries; protects school library staff members and librarians.
Passed Dec 2024
A 230
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Requires DOE to develop model policies for ensuring parental notification of sexually explicit content in curriculum; requires board of education to provide parental notification of sexually explicit content in curriculum.
S 922
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on."Protecting Students from Obscene Material in School Libraries Act."
S 2625
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Creates separate crime for items depicting sexual exploitation or abuse of children; concerns computer generated or manipulated sexually explicit images.
A 2715
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on."Radical Regimes Education Act"; requires age-appropriate instruction on certain governmental regimes in grades nine through 12.
A 912
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on."Protecting Students from Obscene Material in School Libraries Act."
New Mexico
New York
S 08630
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Requires each board of education to adopt a written policy for reconsideration of school library materials and make such policy available on its website; requires such policies to include provisions for the creation of a reconsideration committee to review complaints regarding school library materials; requires the commissioner of education to develop one or more model policies for school districts.
A 09537
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Requires boards of education to adopt written policies for reconsideration of school library materials following complaints regarding such materials; requires the commissioner of education to develop one or more model policies for school districts.
A 05416
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Relates to enacting the "books save lives act"; requires public school libraries receiving state aid to maintain a collection of diverse books.
A 05464
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Establishes requirements for library material in public school libraries and public libraries; requires the development of policies for removal of materials; establishes protections for school library media specialists and librarians against harassment and discrimination in employment related to the refusal to remove library materials.
A 05995
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Prohibits libraries and library systems, including school libraries and school library systems from banning books or other materials based on partisan or doctrinal disapproval.
S 02423
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Prohibits libraries and library systems, including school libraries and school library systems from banning books or other materials based on partisan or doctrinal disapproval.
S 04680
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Requires school boards to make the final decision on whether to keep, remove, or restrict access to an instructional material in a school library; establishes a review process for formal complaints concerning instructional materials that are the subject of complaints.
S 09559
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Prohibits libraries and library systems, including school libraries and school library systems from banning books or other materials based on partisan or doctrinal disapproval.
North Carolina
H 902
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Free to Learn - Library Bill of Rights Act
Passed Apr 2025
H 595
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Parental Rights for Curriculum and Books
Passed Apr 2025
S 49
SignedThe governor has signed the bill into law.Parents' Bill of Rights
Passed Feb 2023
HB 636
AdvancedThe bill has passed one chamber (House or Senate) and moved to the other.Promoting Wholesome Content for Students
North Dakota
Ohio
Oklahoma
SB 1250
AdvancedThe bill has passed one chamber (House or Senate) and moved to the other.Schools; requiring school districts and charter schools to submit certain list of library materials; providing process for reporting violations; providing penalties. Effective date. Emergency.
Passed Mar 2026
HB 2978
FailedThe bill did not pass — it was voted down or expired without action.Schools; library media program; community standards; sexually explicit conduct; effective date.
Passed Mar 2026
HB 1775
SignedThe governor has signed the bill into law.Education; prohibiting certain training for students; prohibiting courses from including certain concept; effective date; emergency.
Passed Mar 2021
SB 1495
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Schools; creating the Age-Appropriate Materials Act; prohibiting public school districts and public charter schools from making certain materials available to students. Effective date.
SB 19
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Schools; requiring school districts and charter schools to submit certain list of library materials; providing process for reporting violations; providing penalties. Effective date. Emergency.
SB 2068
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Schools; requiring each public school district to create a library advisory committee for each grade level. Effective date. Emergency.
Pennsylvania
HB 860
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.In terms and courses of study, providing for prohibited review of curriculum, instructional materials and voluntary inquiry material in public school entities.
SB 230
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.In terms and courses of study, providing for parental control relating to instructional materials and books containing sexually explicit content.
SB 315
SignedThe governor has signed the bill into law.An act amending the act of March 10, 1949 (P.L.30, No.14), entitled "An act relating to the public school system, including certain provisions applicable as well to private and parochial schools; amending, revising, consolidating and changing the laws relating thereto," in preliminary provisions, further providing for Special Education Funding Commission and for minimum number of days or hours; in duties and powers of boards of school directors, providing for admission fees for school-sponsored activities; in intermediate units, further providing for staff; in certification of teachers, further providing for certificates qualifying persons to teach and for instructional certificate grade spans and age levels and duties of department, providing for instructional certificate grade spans and age levels and for State certificate fee reduction, further providing for standard employment application, for career and technical instructional certificate, for program of continuing professional and paraprofessional education and for postbaccalaureate certification, providing for assessment of basic skills, further providing for professional educator discipline fee and providing for career and technical administrative director certification flexibility; in pupils and attendance, further providing for attendance policy at charter, regional charter and cyber charter schools, for procedure when child is truant, for procedure by school when child habitually truant, for procedure upon filing of citation, for penalties for violating compulsory school attendance requirements and for study of truancy procedure, providing for department supports to prevent truancy and further providing for reports to Superintendent of Public Instruction and for exceptional children and education and training; in student supports, further providing for definitions; in school safety and security, further providing for definitions, for School Safety and Security Committee, for school safety and security assessment providers, for School Safety and Security Grant Program, for school safety and security coordinator and for school safety and security training, providing for school safety and mental health grants for 2025-2026 school year and further providing for reporting and memorandum of understanding; in school security, further providing for training, for school resource officers, for school security guards and for duties of commission; in Safe2Say Program, further providing for intent, for definitions, for Safe2Say Program and for annual report; in threat assessment, further providing for definitions, for threat assessment teams and for threat assessment guidelines, training and information materials; in Drug and Alcohol Recovery High School Program, further providing for scope of program and selection of students and for enrollment of students; in evidence-based reading instruction, further providing for definitions and providing for school entity duties related to evidence-based reading instruction, for school entity duties related to reading screening, for reading deficiency identification and parental notification, for reading intervention plans, for grant program, for funding, for reporting, for accountability and for construction; in high schools, further providing for attendance in other districts and providing for Free Application for Federal Student Aid; in interscholastic athletics accountability, further providing for council recommendations and standards; in charter schools, further providing for funding for cyber charter schools, for enrollment and notification and for enrollee wellness checks; in career and technical education, further providing for capital reserve fund for approved purchases of equipment and facility maintenance, for career and technical education equipment grants, for Cosmetology Training through Career and Technical Center Pilot Program and for Barber Training through Career and Technical Center Pilot Program; providing for Nursing Shortage Assistance Program; in community colleges, further providing for financial program and reimbursement of payments; in the State System of Higher Education, further providing for definitions and for Grow Pennsylvania Merit Scholarship Program; in educational tax credits, further providing for limitations; in higher education accountability and transparency, further providing for exit counseling; in miscellaneous provisions relating to institutions of higher education, repealing provisions relating to State-related university performance-based funding model, further providing for prohibition on scholarship displacement at public institutions of higher education and providing for cooperation and for State scholarship renewals; in institutions of higher education, further providing for powers and duties of State Board of Higher Education, for definitions, for Performance-based Funding Council and for public institution of higher education reporting, providing for State-related University Performance Fund, for performance-based funding formula and for public accountability and further providing for agency duties, for grant priority and for report; in Ready-to-Succeed Scholarship, further providing for agency; in funding for public libraries, providing for State aid for fiscal year 2025-2026; in reimbursements by Commonwealth and between school districts, further providing for student-weighted basic education funding beginning with 2023-2024 school year, for extraordinary special education program expenses, for assistance to school districts declared to be in financial recovery status or identified for financial watch status and for Ready-to-Learn Block Grant; in construction and renovation of buildings by school entities, further providing for applicability; abrogating regulations; and making an editorial change.
Rhode Island
South Carolina
Tennessee
SB 0701
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.AN ACT to amend Tennessee Code Annotated, Title 10 and Title 49, relative to libraries.
Passed Feb 2025
HB 0843
SignedThe governor has signed the bill into law.Age-Appropriate Materials Act Amendment (HB 843)
Passed Apr 2023390 linked books
HB 0715
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.AN ACT to amend Tennessee Code Annotated, Title 10 and Title 49, relative to libraries.
Texas
SB 13
EffectiveThe law is now in effect and enforceable.Relating to public school library materials, including the establishment of school library advisory councils.
Passed May 20251000 linked books
HB 3225
AdvancedThe bill has passed one chamber (House or Senate) and moved to the other.Relating to the restriction of access by minors to sexually explicit materials in municipal public library collections; providing a civil penalty.
Passed May 2025
SB 12
SignedThe governor has signed the bill into law.Relating to parental rights in public education, to certain public school requirements and prohibitions regarding instruction, diversity, equity, and inclusion duties, and social transitioning, and to student clubs at public schools.
Passed Mar 202515 linked books
SB 1621
SignedThe governor has signed the bill into law.Relating to prosecution and punishment of certain criminal offenses prohibiting sexually explicit visual material involving depictions of children, computer-generated children, or other persons; creating criminal offenses; increasing criminal penalties.
Passed Mar 2025
HB 900
SignedThe governor has signed the bill into law.Relating to the regulation of library materials sold to or included in public school libraries.
Passed Apr 2023163 linked books
HB 3979
SignedThe governor has signed the bill into law.Relating to the social studies curriculum in public schools.
Passed May 2021
HB 7
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Relating to parental rights in public education, to the creation of the office of inspector general at the Texas Education Agency, and to the reporting of certain misconduct and child abuse and neglect; creating a criminal offense.
SB 2101
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Relating to the prohibition of access by minors to sexually explicit materials in municipal public library collections; providing a civil penalty.
HB 5460
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Relating to the display of sexually explicit material in public libraries.
HB 5021
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Relating to the standards for public school library materials.
HB 183
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Relating to the regulation and the review of certain library materials included in public school libraries.
HB 4056
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Relating to school district policies regarding the selection, removal, and replacement of library materials.
HB 4198
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Relating to the standards for a school district's library collection development policies; providing a civil penalty.
HB 4354
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Relating to access to certain public school library materials.
HB 4448
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Relating to an automated artificial intelligence review of library material purchased by public schools; providing an administrative penalty.
HB 4911
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Relating to prosecution and punishment of certain criminal offenses prohibiting sexually explicit visual material involving depictions of children, computer-generated children, or other persons; creating criminal offenses; increasing criminal penalties.
HB 5485
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Relating to the standards for a school district's library collection development policies; providing a civil penalty.
US
HB 5
AdvancedThe bill has passed one chamber (House or Senate) and moved to the other.Parents Bill of Rights Act
Passed Mar 2023
HB 7691
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Fight Book Bans Act
HB 7661
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Stop the Sexualization of Children Act
HB 6440
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Right to Read Act of 2025
SB 3365
IntroducedThe bill has been filed in a legislative chamber but has not yet been voted on.Right to Read Act of 2025
Utah
HB 0517
FailedThe bill did not pass — it was voted down or expired without action.Sensitive Materials
Passed Mar 2026
SB 0253
FailedThe bill did not pass — it was voted down or expired without action.Library Materials Amendments
Passed Mar 2026
HB 0029
ChallengedA lawsuit has been filed challenging this law's constitutionality.Sensitive Material Review Amendments
Passed Jan 202428 linked books
HB 0374
SignedThe governor has signed the bill into law.Sensitive Materials in Schools
Passed Mar 202228 linked books
HB 197
FailedThe bill did not pass — it was voted down or expired without action.School Materials Amendments
Vermont
Virginia
HB 1499
SignedThe governor has signed the bill into law.DOE; policies relating to instructional material that contains sexually explicit content.
Passed Feb 2026
SB 19
SignedThe governor has signed the bill into law.DOE; policies relating to instructional material that contains sexually explicit content.
Passed Jan 2026
Washington
West Virginia
Wisconsin
Wyoming
Legislative data provided by LegiScan. Licensed under CC BY 4.0.