Gerstenfeld, Arthur
California Addison-Wesley Publishing , 1970
Buku Teks
Jacobstein, J. Myron
Foundation press, 1979
Buku Teks
Bos, A. M.
Institute of Sociology Grote, 1979
Buku Teks
Osbeck, Mark K., author
Thomson/West, 2010
Buku Teks
Surrency, Erwin C.
An Oceana Publication, 1966
Buku Teks