The Free On-line Dictionary of Computing (30 December 2018):

Yourdon, Inc.

    The company founded in 1974 by Edward Yourdon to
   provide educational, publishing, and consulting services in
   state-of-the-art software engineering technology.  Over the
   next 12 years, the company grew to a staff of over 150 people,
   with offices throughout North America and Europe.  As CEO of
   the company, Yourdon oversaw an operation that trained over
   250,000 people around the world; the company was sold in 1986
   and eventually became part of CGI, the French software
   company that is now part of IBM.  The publishing division,
   Yourdon Press (now part of Prentice Hall), has produced over
   150 technical computer books on a wide range of software
   engineering topics; many of these "classics" are used as
   standard university computer science textbooks.

   (1995-04-16)