Bodnar, George H.
Prentice-Hall, 2001
Buku Teks
Romney, Marshall B.
Prentice-Hall, 2003
Buku Teks
Page, John R., 1949-
Prentice-Hall, 1987
Buku Teks
Bodnar, George H.
Prentice-Hall International, 1998
Buku Teks
Page, John R., 1949-
Prentice-Hall International, 1992
Buku Teks