1. J. Gougen Jr., “Logic of Inexact Concepts”, Synthese 19, 325–373 (1968–69)
2. J. Gougen Jr., see also Int. J. of Man-Machine Studies 6, 513–561 (1974).
3. G. Wohol, D. Grottkind & H. D’Angelo, Measures of Merit for Command & Control, MTR-8217, Mitre-Bedford (15 January, 1981).
4. W.J.M. Happel, COMIL; The COMO-III Input Language, STC TM-597, Shape Technical Centre, The Hague (April 1979).
5. I.L. Janis & L. Mann, Decision Making, Free Press division of McMillan Publishers, New York City (1979).