Hampton, David R., author
McGraw-Hill, 1986
Buku Teks
Rubenstein, David, author
Original Publishing., 1976
Buku Teks
Kluwer Academic Publishers, 1989
Buku Teks
Jannis, C. Paul
N.Y. John Weley & Sons c. , 1980
Buku Teks
Hachenburger, Petra
Routledge, 2000
Buku Referensi