Cullingworth, J.B.
Allen & Unwin, 1973
Buku Teks
Henslin, James M.
McGraw-Hill, 1983
Buku Teks
Etzioni, Amitai
Prentice-Hall, 1976
Buku Teks
Kornblum, William
Prentice-Hall, 1992
Buku Teks
Scarpitti, Frank R.
Holt, Rinehart and Winston, 1974
Buku Teks