• The library Copyright Reference Guide has relevant sections on the public domain and state and federal government materials.
• The HathiTrust U.S. Federal Government Documents Initiative help page answers frequently asked questions about their government documents.
• U.S. Federal Government Documents Registry (which is in beta testing) lets you search for metadata on U.S. federal documents produced from 1789 to the present.

For more information about government documents, contact Sanga Sung.