Klein, Philip
Jossey-Bass, 1968
Buku Teks
Leo C. Brown [and others] of the Institute of Social Order, St. Louis University
ill Loyola University Press , 1954
Buku Teks
Prentice-Hall, 1970
Buku Teks
Labovitz, Sanford, author
McGraw-Hill, 1971.
Buku Teks
Institute of Social Science, University of Tokyo,
Majalah, Jurnal, Buletin