Davis, Richard A.
Wm.C. Brown Publishers, 1991
Buku Teks
Gross, M. Grant
Prentice-Hall, 1995
Buku Teks
Hutabarat, Sahala
UI-Press, 1985
Buku Teks
Stowe, Keith S., 1943-
John Wiley & Sons, 1996
Buku Teks
Thurman, Harold U.
Merril Publishing company , 1988
Buku Teks