Ellis, Norman Dean, 1933-. The Relationship between Identifiable Attributes and Decision-Making Ability of Purchasing Personnel as Measured by the Results of a Management Game, dissertation, May 1973; (https://digital.library.unt.edu/ark:/67531/metadc164597/m1/27/: accessed May 19, 2019), University of North Texas Libraries, Digital Library, digital.library.unt.edu; .