Madura, Jeff
South-Western College, 1998
Buku Teks SO
O`Connor, Dennis J.
Macmillan, 1990
Buku Teks SO
Eun, Cheol S.
Irwin McGraw-Hill, 2001
Buku Teks
Henning, Charles W.
McGraw-Hill Kogakusha, 1978
Buku Teks
Rodriguez, Rita M.
Prentice-Hall, 1976
Buku Teks