Walton, Grant W., author
Routledge, 2018
Buku Teks
Lane, Max
Institute of Southeast Asian Studies , 2014
eBooks
Thomas, A.J.
Pitman and Son , 1967
Buku Teks
Kramer, Dale, author
Cambridge University Press, 1991
Buku Teks
Thomas, David, author
Macmillan Education , 1990
Buku Teks