Digital Press, 1983
Buku Teks
Guiltinan, Joseph P.
McGraw-Hill , 1982
Buku Teks
McGraw-Hill, 1972.
Buku Teks
Leininger, Madeleine M., author
John Wiley & Sons, 1978
Buku Teks
edited by Gerald E. Caiden and Heinrich Siedentopf
LexingtonBooks, 1982
Buku Teks