Artikel Jurnal
Wardlaw, Gordon M., 1912-1989, author
McGraw-Hill, 2004
Buku Teks
R.S. Jassal, Joint Secretary, External Publicity Division,
Majalah, Jurnal, Buletin
Rosenberg, Nathan, author
Cambridge University Press, 1976
Buku Teks
Cuff, E.C., author
Routledge, 1995
Buku Teks