https://datatracker.ietf.org/doc/html/rfc822
RFC 822 - STANDARD FOR THE FORMAT OF ARPA INTERNET TEXT MESSAGES
STANDARD FOR THE FORMAT OF ARPA INTERNET TEXT MESSAGES (RFC 822, ; obsoleted by RFC 2822)
rfc 822text messagesstandardformatarpa
https://www.rfc-editor.org/info/rfc822
Information on RFC 822 ยป RFC Editor
rfc 822informationeditor
https://datatracker.ietf.org/doc/html/rfc1494
RFC 1494 - Equivalences between 1988 X.400 and RFC-822 Message Bodies
Equivalences between 1988 X.400 and RFC-822 Message Bodies (RFC 1494, )
rfcmessagebodies