Salvia, John, author
Houghton Miffiln, 1991
Buku Teks
Anderson, Alan J.B., Author
Chapman & Hall, 1994
Buku Teks
edited by Joy Hendry
Routledge, 1998
Buku Teks
Sederberg, Peter C.
Chandler & Sharp Publishers, 1977
Buku Teks
Lang, Margaret, author
Routledge, 2001
Buku Teks