Copyright Term and the Public Domain in the United States chart
https://guides.library.cornell.edu/copyright/publicdomain
This quick guide helps determine public domain status (updated yearly), and also includes information on sound recordings and architecture.
The Committee on Intellectual Property's section of the College Art Association website
http://www.collegeart.org/standards-and-guidelines/intellectual-property
Resources on U.S. copyright: Fundamentals and Documents; Image Sources and Rights Clearance Agencies; Fair Use Guidelines, Practices, and Policies; Copyright Outside the United States and Legal Assistance.
University of Minnesota Libraries Copyright Services, Using Copyrightable Materials
https://www.lib.umn.edu/copyright/useoverview
Includes "Thinking Through Fair Use," a worksheet that helps you conduct a four-factor review of your proposed fair use.
Teaching Copyright
http://www.teachingcopyright.org/
This curriculum is designed to give teachers a comprehensive set of tools to educate students about copyright while incorporating activities that exercise a variety of learning skills.
Orphan Works: Statement of Best Practices
http://www2.archivists.org/groups/intellectual-property-working-group/orphan-works-statement-of-best-practices
This statement from the Society of American Archivists describes the best practices regarding reasonable efforts to identify and locate rights holders.
Reproduction of Copyrighted Works by Educators and Librarians
http://www.copyright.gov/circs/circ21.pdf
Provides information regarding reproductions and fair use for purpose of study, research, and teaching.
American Library Association Copyright Advisory Network
http://librarycopyright.net/resources/genie/index.php
Resource includes: Copyright Genie, to help determine if a work is covered by copyright and calculate its term of protection.
American Library Association Copyright Advisory Network (Fair Use)
http://librarycopyright.net/resources/fairuse/index.php
Resource includes: Fair Use Evaluator, to help you determine determine the "fairness" of a use under the U.S. Copyright Code.
Foreign Copyright Chart
http://chart.copyrightdata.com/ch08A.php#top
A quick guide of copyright law for non-US copyrighted works
Is it in the Public Domain?
https://www.law.berkeley.edu/files/FINAL_PublicDomain_Handbook_FINAL(1).pdf
A handbook for evaluating the copyright status of a work created in the United States between January 1, 1923 and December 31, 1977.
Copyright & Cultural Institutions: Guidelines for Digitization for U.S. Libraries, Archives, & Museums
https://ecommons.cornell.edu/bitstream/handle/1813/14142/Hirtle-Copyright_final_RGB_lowres-cover1.pdf?sequence=2&isAllowed=y
Provides guidelines and best practices for digitizing archival collections; includes case studies.
Rights and Reproductions: The Handbook for Cultural Institutions
https://rowman.com/ISBN/9781538112656/Rights-and-Reproductions-The-Handbook-for-Cultural-Institutions-Second-Edition
Offers rights and reproduction guidelines, standards, and best practices; includes topics such as fair use, Creative Commons, open access, and RightsStatements.org.
Code of Best Practices in Fair Use for the Visual Arts
https://www.collegeart.org/pdf/fair-use/best-practices-fair-use-visual-arts.pdf
Provides best practices in assessing fair use in visual arts.
Visual Resources Association: Statement on the Fair Use of Images for Teaching, Research and Study
https://online.vraweb.org/index.php/vrab/article/view/139
Describes six uses of copyrighted still images that the Visual Resources Association believes fall within the U.S. fair use doctrine.