Shostak, Arthur B.
Macmillan Publishing Company, 1974
Buku Teks
by Thomas J. Sullivan ... [and others]
John Wiley & Sons, 1980
Buku Teks
May, John D.
Duxbury Press, 1972
Buku Teks
Ackoff, Russell Lincoln, 1919-, author
John Wiley & Sons, 1974
Buku Teks
edited by David Popenoe
Rutgers University Press, 1969
Buku Teks