Soja, Edward W.
Blackwell, 2000
Buku Teks SO
Jarvis, Helen
Prentice-Hall, 2001
Buku Teks SO
edited by Gary Gappert and Richard V. Knight
Sage, 1982
Buku Teks SO
edited by Andrew Blowers, Chris Hammett and Philip Sarre
Hutchinson Educational in association with the Open University Press, 1974
Buku Teks SO
Gutkind, E.A.
Free Press of Glencoe, 1963
Buku Teks SO