From this page you can download several older papers documenting the earlier development and use of the Penman Upper Model.

• postscript and pdf (converted from LaTeX and so not pretty) versions of the paper:
  "Upper Modeling: A general organization of knowledge for natural language processing" (Bateman, 1990)

Postscript version (compressed with gzip)
Acrobat PDF version

• A paper with considerably more detail, as well as a comparison with other approaches in natural language processing, is available at the cmp-lg archive: The Theoretical Status of Ontologies in Natural Language Processing (Bateman, 1997).

• The orignal 1988-1990 documentation of the original Upper Model:
  John Bateman, Robert Kasper, Johanna Moore and Richard Whitney (1990) A general organization of knowledge for natural language processing: The Penman Upper Model. Technical Report. Information Sciences Institute. Marina del Rey, California
  has now been scanned in as a pdf