usefor-article-09 February 2003

6.10.  References

   The References-header lists CFWS-separated message identifiers of
   precursors. The content syntax makes use of syntax defined in [RFC
   2822], subject to the same revisions as in section 5.3.

      header              =/ References-header
      References-header   = "References" ":" SP References-content
      References-content  = [CFWS] msg-id *( CFWS msg-id ) [CFWS]

        NOTE: This differs from the syntax of [RFC 2822] by requiring at
        least one CFWS between the msg-ids (a SP at this point was an
        [RFC 1036] requirement).

   A followup MUST have a References-header, and an article that is not
   a followup MUST NOT have a References-header. In a followup, if the
   precursor did not have a References-header, the followup's
   References-content MUST be formed by the message identifier of the
   precursor. A followup to an article which had a References-header
   MUST have a References-header containing the precursor's References-
   content (subject to trimming as described below) plus the precursor's
   message identifier appended to the end of the list (separated from it
   by CFWS).

   Followup agents SHOULD NOT trim message identifiers out of a
   References-header unless the number of message identifiers exceeds
   21, at which time trimming SHOULD be done by removing sufficient
   identifiers starting with the second so as to bring the total down to
   21 (but the first message identifier MUST NOT be trimmed). However,
   it would be wrong to assume that References-headers containing more
   than 21 message identifiers will not occur.

--- ../usefor-article-08/References.out          August 2002
+++ ../usefor-article-09/References.out          February 2003
@@ -6,7 +6,6 @@
 
       header              =/ References-header
       References-header   = "References" ":" SP References-content
-                     *( ";" other-parameter )
       References-content  = [CFWS] msg-id *( CFWS msg-id ) [CFWS]
 
         NOTE: This differs from the syntax of [RFC 2822] by requiring at