Binary Message Forms in Computer
RFC 31, “Binary Message Forms in Computer”, is an Unknown document published in February 1968 by D. Bobrow, W.R. Sutherland. The canonical text is published by the RFC Editor.
What “Unknown” means
The standards-track status of this early RFC was never formally classified.
The canonical text of RFC 31 is hosted at rfc-editor.org. Available in TXT,HTML.