The Conference Board; editor, Edward C. Bursk
The Free Press, 1973
Buku Teks
Saaty, Thomas L., author
Praeger, 1990
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United Nations Departemen of Public Information, 1990
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Handelman, Howard, author
Pearson/Prentice Hall, 2006
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Nevid, Jeffrey S.
Pearson Education International, 2008
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