Fax standards and protocols This page discribes different fax modem protocols, including Group 3 protocol, and the evolution of fax modems.
NIST Group 3 protocol machine specifications Contains the text of the Federal Information Processing Standards Publication 147 describing machine specifications for Group 3 facsimile apparatus for use over voice band analog circuits.
RFC 2301 Request for Comments document for the File Format for Internet Fax.
