Loury, Glenn C.
Buku Teks
edited by W.A.V. Clark and Eric G. Moore
Sage, 1980
Buku Teks SO
Lipset, Seymour Martin
University of California, 1967
Buku Teks SO
Davies, Ioan
Pall Mall Press, 1970
Buku Teks SO
Matras, Judah
Prentice-Hall, 1975
Buku Teks SO