Bellemore, Douglas H.
South-Western Publishing, 1974
Buku Teks SO
Badger, Ralph Eastman, 1890-
Prentice-Hall, 1951
Buku Teks
Engel, Louis
Bantam Book, 1967
Buku Teks
Fischer, Donald E.
Prentice-Hall, 1991
Buku Teks
Suad Husnan
UPP AMP YKPN , 1996
Buku Teks