Gottdiener, Mark, author
Westview Press, 2015
Buku Teks
Abrahamson, Mark, author
Cambridge University Press, 2014
Buku Teks
Flanagan, William G., author
Allyn and Bacon, 1990
Buku Teks
edited by R.E. Pahl
Pergamon Press, 1968
Buku Teks
Mann, Peter H., author
Humanities Press, 1965
Buku Teks