| Created |
| Associated with RFC-987 |
| Associated with RFC 987 |
| Associated with RFC 1026 |
| Associated with X.400 |
| Associated with RFC 1138 |
| Associated with RFC 1148 |
| Associated with RFC 1328 |
| Associated with RFC 1327 |
| Associated with RFC 1405 |
| Associated with RFC 1465 |
| Associated with RFC 1494 |
| Associated with RFC 1495 |
| Associated with RFC 1496 |
| Associated with RFC 1506 |
| Associated with RFC 1615 |
| Associated with RFC 1616 |
| Associated with RFC 1648 |
| Associated with RFC 1664 |
| Associated with RFC 1685 |
| Associated with RFC 1838 |
| Associated with RFC 1502 |
| Associated with RFC 2156 |
| Associated with MIXER |
| Associated with RFC 2157 |
| Associated with RFC 2158 |
| Associated with RFC 2159 |
| Associated with RFC 2162 |
| Associated with RFC 2163 |
| Associated with RFC 2164 |
| Associated with X400- |
| Associated with X400-* |
| Associated with X400 |
| Associated with X400-*: |
| Associated with Discarded-X400-*: |
| Associated with Discarded-X400-* |
| Associated with Discarded-X400 |
| Associated with Discarded-X400- |
| Associated with P1-* |
| Associated with P1-*: |
| Associated with P1 |
| Associated with P1- |
| Associated with Delivery-Report-Content-*: |
| Associated with Delivery-Report-Content-* |
| Associated with Delivery-Report-Content |
| Associated with Delivery-Report-Content- |