[4] RFC 976 - UUCP mail interchange format standard, 1/24/2021, 1:09:17 PM, 3/10/2021, 6:35:43 AM https://tools.ietf.org/html/rfc976
[37] RFC 1137 - Mapping between full RFC 822 and RFC 822 with restricted encoding, 1/31/2021, 11:41:44 AM, 3/13/2021, 7:21:00 AM https://tools.ietf.org/html/rfc1137
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