File name confusion with topicAttr.mod

In catalog-dita.txt the file "topicAttr.ent" is referenced twice, but it
is missing from the ditribution.  "topicAttr.mod" comes with dtd.zip,
but it is not reference in the catalog file, and the comment in this
file misleadingly says:

PUBLIC "-//OASIS//ENTITIES DITA Topic Class//EN"
      Delivered as file "topic_class.ent"

I'd appreciate clarification.  Regards,
Karl

-- 
Karl Eichwalder
R&D / Documentation                         SUSE Linux Products GmbH

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