Spulber, Nicolas
Indiana Univeristy Press , 1965
Buku Teks
Frederick A. Praeger Publishers, [date of publication not identified]
Buku Teks
Campbell, Robert W., author
Houghton Mifflin , 1960
Buku Teks
Feiwel, George R.
Praeger Pub., 1972
Buku Teks
edited by Morris Bornstein, Daniel R. Fusfeld
Richard D. Irwin, 1966
Buku Teks