Pillar, Paul R.
Princeton University Press , 1983
Buku Teks SO
T. David Marson; James D. Meernik, editor
Routledge, 2006
Buku Teks SO
Conlin Joseph R
The Glencoe Press, 1968
Buku Teks SO
Thomson, David
Kegan Paul, Trench, Trubner, 1945
Buku Teks SO
Reves, Emery
Elsevier, 1947
Buku Teks