[1] RFC 987 - Mapping between X.400 and RFC 822, , https://tools.ietf.org/html/rfc987
[2] RFC 1026 - Addendum to RFC 987: (Mapping between X.400 and RFC-822), , https://tools.ietf.org/html/rfc1026
[3] RFC 1138 - Mapping between X.400(1988) / ISO 10021 and RFC 822, , https://tools.ietf.org/html/rfc1138
[5] RFC 1148 - Mapping between X.400(1988) / ISO 10021 and RFC 822, , https://tools.ietf.org/html/rfc1148
[7] RFC 1327 - Mapping between X.400(1988) / ISO 10021 and RFC 822, , https://tools.ietf.org/html/rfc1327
[8] RFC 1328 - X.400 1988 to 1984 downgrading, , https://tools.ietf.org/html/rfc1328
[9] RFC 1330 - Recommendations for the Phase I Deployment of OSI Directory Services (X.500) and OSI Message Handling Services (X.400) within the ESNET Community, , https://tools.ietf.org/html/rfc1330
[10] RFC 1405 - Mapping between X.400(1984/1988) and Mail-11 (DECnet mail), , https://tools.ietf.org/html/rfc1405
[11] RFC 1465 - Routing Coordination for X.400 MHS Services Within a Multi Protocol / Multi Network Environment Table Format V3 for Static Routing, , https://tools.ietf.org/html/rfc1465
[12] RFC 1494 - Equivalences between 1988 X.400 and RFC-822 Message Bodies, , https://tools.ietf.org/html/rfc1494
[13] RFC 1495 - Mapping between X.400 and RFC-822 Message Bodies, , https://tools.ietf.org/html/rfc1495
[14] RFC 1496 - Rules for downgrading messages from X.400/88 to X.400/84 when MIME content-types are present in the messages, , https://tools.ietf.org/html/rfc1496
[24] RFC 1502 - X.400 Use of Extended Character Sets, , https://tools.ietf.org/html/rfc1502
[15] RFC 1506 - A Tutorial on Gatewaying between X.400 and Internet Mail, , https://tools.ietf.org/html/rfc1506
[16] RFC 1615 - Migrating from X.400(84) to X.400(88), , https://tools.ietf.org/html/rfc1615
[17] RFC 1616 - X.400(1988) for the Academic and Research Community in Europe, , https://tools.ietf.org/html/rfc1616
[18] RFC 1648 - Postmaster Convention for X.400 Operations, , https://tools.ietf.org/html/rfc1648
[19] RFC 1664 - Using the Internet DNS to Distribute RFC1327 Mail Address Mapping Tables, , https://tools.ietf.org/html/rfc1664
[20] RFC 1685 - Writing X.400 O/R Names, , https://tools.ietf.org/html/rfc1685
[21] RFC Errata Report » RFC Editor, https://www.rfc-editor.org/errata_search.php?rfc=1685
[22] RFC 1838 - Use of the X.500 Directory to support mapping between X.400 and RFC 822 Addresses, , https://tools.ietf.org/html/rfc1838
[23] RFC 1922 - Chinese Character Encoding for Internet Messages, , https://tools.ietf.org/html/rfc1922#section-6
[27] RFC 2156 - MIXER (Mime Internet X.400 Enhanced Relay): Mapping between X.400 and RFC 822/MIME, , https://tools.ietf.org/html/rfc2156
[28] RFC 2157 - Mapping between X.400 and RFC-822/MIME Message Bodies, , https://tools.ietf.org/html/rfc2157
[29] RFC Errata Report » RFC Editor, https://www.rfc-editor.org/errata_search.php?rfc=2157
[30] RFC 2158 - X.400 Image Body Parts, , https://tools.ietf.org/html/rfc2158
[31] RFC 2159 - A MIME Body Part for FAX, , https://tools.ietf.org/html/rfc2159
[32] RFC 2162 - MaXIM-11 - Mapping between X.400 / Internet mail and Mail-11 mail, , https://tools.ietf.org/html/rfc2162
[33] RFC 2163 - Using the Internet DNS to Distribute MIXER Conformant Global Address Mapping (MCGAM), , https://tools.ietf.org/html/rfc2163
[34] RFC 2164 - Use of an X.500/LDAP directory to support MIXER address mapping, , https://tools.ietf.org/html/rfc2164
[35] RFC 4249: Implementer-Friendly Specification of Message and MIME-Part Header Fields and Field Components, https://www.rfc-editor.org/rfc/rfc4249.html#section-3.1.2.2.7
[36] RFC 4450: Getting Rid of the Cruft: Report from an Experiment in Identifying and Reclassifying Obsolete Standards Documents, , https://www.rfc-editor.org/rfc/rfc4450.html