Kent, Alexandra
ISEAS, 2007
Buku Teks
design by Saiful Anwar Yahya ; compiled by Krishna Gopal Rampal
Raja Thuraisingham, 2008
Buku Referensi
Ryan, N.J
Oxford University Press, 1970
Buku Teks
The Straits Times Press, 1971
Buku Teks
Yaman Ibrahim, author
Neoedition, 2010
Buku Referensi