Gabel, Creighton
Holt, Rinehart and Winston, 1967
Buku Teks
Herskovits, Melville J. (Melville Jean), 1895-1963, author
WW Norton, [Date of publication not identified]
Buku Teks
Tavistock Publications, 1970
Buku Teks
Nash, Manning
Chandler Publishing Company, 1966
Buku Teks
Rouse, Irving
McGraw-Hill, 1972
Buku Teks