Wolk, Harry L.
PWS-Kent Publishing Company, 1988
Buku Teks
Frigon, Normand L.
N.Y. American Management Association , 1996
Buku Teks
Raper, Arthur F
Cornell University Press, 1970
Buku Teks
Wiley-Interscience, 1969
Buku Teks
Glasgow, Joshua, author
Routledge, 2009
Buku Teks