Nevaer, Louis E.V.
Quorum Books , 1987
Buku Teks
Vaughn, Donald E., author
Prentice-Hall, 1997
Buku Teks
Polakoff, Murray Emanuel, 1922-, author
Houghton Miffiln, 1970
Buku Teks
edited by Donald R. Fraser and Peter S. Rose
Business Publications, 1980
Buku Teks
Goldsmith, Raymond W.
Columbia University Press , 1965
Buku Teks