Tomlinson, Jim, author
Methuen, 1981
Buku Teks
Alford, B.W.E., author
Macmillan, 1988
Buku Teks
Hubbard, G. E., author
International Secretariat Institute of Pasific Relations , 1943
Buku Teks
Rifki Firdaus, author
2010
UI - Skripsi (Open)
Mansfield, Edwin, author
W.W. Norton, 1974
Buku Teks