Epps, Edgar G.
Winthrop Publisher,INC, 1973
Buku Teks
edited by Edgar T. Thompson, Robert E. Park
Duke University Press, 1939
Buku Teks
Brown, Ina Corinne
Prentice-Hall, 1973
Buku Teks
Charles A Gallagher, editor
McGraw-Hill, 2012
Buku Teks
Schrieke, Bertram Johannes Otto, author
Viking Press, 1936
Buku Teks