Baron, Naomi S., author
Routledge , 2001
Buku Teks
Natelson, Morris, author
Fairchild Publications, 1962
Buku Teks
Aitchison, James, author
Cassell, 1994
Buku Teks
OConnor, Frederick H., author
National Textbook Company, 1990
Buku Referensi
Bex, Tony
Routledge , 1996
Buku Teks