Passante, Christopher K., author
Prenada Media Group, 2008
Buku Teks
Whale, John
Macmillan, 1972
Buku Teks
Ahuja, B. N., author
Surjeet Publications , 1992
Buku Teks
Christhopher, C.
Anmol Publicatioans PVT. Ltd, 1997
Buku Teks
edited by Barbie Zelizer, Stuart Allan
Routledge, 2002
Buku Teks