Gelineau, R. Phyllis, author
Cengage Learning , 2012
Buku Teks
Ian Thomson, editor
McGraw-Hill Education, 2010
Buku Teks
Cambridge University Press, 2010
eBooks
Copeland, Richard W., author
Macmillan, 1970
Buku Teks
Ellya Mutia Fansuraini, author
Fakultas Ilmu Sosial dan Ilmu Politik Universitas Indonesia, 2016
UI - Skripsi (Membership)