Heather, Ken
Prentice-Hall, 2002
Buku Teks
Thompson, Arthur A., 1940-, author
Prentice-Hall, 1989
Buku Teks
Solingen, Etel, author
Rotledge, 2015
Buku Teks
Savage, Christopher I., author
Hutchinson, 1975
Buku Teks
Speight, H., author
Macmillan, 1970
Buku Teks