The Princeton Language Institute (the Princeton Language Institute)

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  Roget's 21st Century Thesaurus: In Dictionary Form
  by Barbara Ann Kipfer, Princeton Language Institute, Peter Mark Roget, the Princeton Language Institute
  Softcover, Bantam Dell Pub Group, ISBN 0385312555 (0-385-31255-5)
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  Roget's 21st Century Thesaurus: In Dictionary Form The Essential Reference for Home, School, or Office
  by Barbara Ann Kipfer
  Softcover, Bantam Dell Pub Group, ISBN 0385338953 (0-385-33895-3)