List of resources for determining copyright status:
- http://www.copyright.gov/records/, U.S. Copyright Office (1978+)
- http://books.google.com/googlebooks/copyrightsearch.html, Catalog of Copyright Entries (1922-1977)
- licensing companies, such as the Copyright Clearance Center, ASCAP, BMI, Harry Fox, etc.
- Intellectual Property Policy at IU: http://policies.iu.edu/policies/categories/administration-operations/intellectual-property/intellectual-property.shtml
- Indiana University Libraries' Copyright web pages: http://www.libraries.iub.edu/?pageId=5318
- Cornell University Copyright Information Center, Guide to Copyright Term and the Public Domain in the United States: http://copyright.cornell.edu/resources/docs/copyrightterm.pdf