HathiTrust is a shared digital repository that brings together the collections (including the US government documents collections) of partner institutions. HathiTrust is the best place to search for an older government reports, but keep in mind it can be difficult to track down.
Copyrighted items are available for full-text search in the HathiTrust Digital Library and can be helpful in the creation of a bibliography.
Items in the public domain or available through Creative Commons licensing are marked “Full view” in the online catalog at https://www.hathitrust.org.
Because the University of Delaware is a HathiTrust member, you may log in to HathiTrust using your UDelNet ID & download full PDFs of "Full View" items.