Summers, Vivian, author
Penguin Books, 1991
Buku Teks
Gilbert, Judy B., author
Cambridge University Press, 2005
Buku Teks
Shidle, Norman G., author
McGraw-Hill, 1951
Buku Teks
Flesch, Rudolf, author
Harper & Row, 1951
Buku Teks
Henny Marlyna, author
Fakultas Ilmu Sosial dan Ilmu Politik Universitas Indonesia, 2004
UI - Skripsi (Membership)