Sax, Sidney
Allen & Unwin , 1990
Buku Teks
Hicks, Lanis L.
Jones & Bartlett Learning, 2014
Buku Teks SO
Folland, Sherman
Prentice-Hall, 2001
Buku Teks SO
Ruchlin, Hirsch S.
Charles C. Thomas, 1973
Buku Teks SO
Feldstein, Paul J.
Delmar, 2012
Buku Teks SO