Nowak, Norman D., author
Praeger, 1970
Buku Teks
Pike, Fredrick B.
University of Notre Dame Press, 1963
Buku Teks
Nurrika Anggraini, author
Universitas Indonesia, 2010
UI - Tesis (Open)
Princeton University Press, 1944
Buku Teks
Daniel, Hawthorne, author
G.P. Putnam's Sons , 1943
Buku Teks