17 USC § 107 – Limitations on exclusive rights: Fair use
US Copyright Office page on Fair use
Stanford Libraries web page on copyright and fair use.
Columbia University Library fair use check list.
Chilling Effects Frequently Asked Questions (and Answers) about Copyright and Fair Use
Center for Social Media page on codes for fair use.
American Library Association: What is Fair Use?
USPTO Final Report to the Commissioner on the Conclusion of the Conference on Fair Use. November 1998 (PDF)