Lanier, Susan
Regents/Prentice Hall, 1992
Buku Teks
Boockholdt, James L.
Irwin, 1996
Buku Teks
Moscove, Stephen A.
John Wiley & Sons, 1997
Buku Teks
Klooster, Dale H.
South-Western Publishing, 1983
Buku Teks
Klooster, Dale H.
South-Western, 1990
Buku Teks