Conceptual Graphs:
   cg@cs.umn.edu

   Conceptual Graphs are a general semantic network representation of
   knowledge invented by John Sowa. They have the expressive power of
   logic, but with an easy mapping to natural language.

   See, for example,

      John F. Sowa, "Conceptual Structures: Information Processing in
      Man and Machine", Addison-Wesley, Reading, Mass, 1984.

      John Florian Sowa, "Knowledge Representation", forthcoming. 

   To join, contact tjan@cs.umn.edu. 

KQML:
   kqml@cs.umbc.edu

   Discussion of the conceptual design and use of KQML (Knowledge
   Query and Manipulation Language), a protocol for exchanging
   information and knowledge.

   To subscribe, send mail to majordomo@cs.umbc.edu
   with 
     subscribe kqml
   in the message body.

   The mailing list archives are accessible by WWW to
      http://www.cs.umbc.edu/kqml/mail/
   The KQML WWW page is
      http://www.cs.umbc.edu/kqml/
   and is also accessible by anonymous ftp to
      ftp.cs.umbc.edu:/pub/kqml/

Knowledge Sharing:
   srkb@cs.umbc.edu

   For the shared-ontologies part of the Knowledge Sharing Effort of ARPA.  

   To join send a message to majordomo@cs.umbc.edu with 
      subscribe srkb
   in the message body.

Interlingua:
   interlingua@isi.edu

   For the KIF language (Knowledge Interchange Format) of the ARPA
   Knowledge Sharing Effort. KIF resembles predicate logic with many
   added parentheses, plus some set theory.