Murphy, Raymond, author
Cambridge University Press, 1998
Buku Teks
Hewings, Martin, author
Cambridge University Press, 2005
Buku Teks
Gilbert, Judy B., author
Cambridge University Press, 2005
Buku Teks
Hamilton, Mark, author
Neo-tech books, 2000
Buku Teks
Jones, Kenneth L.
Harper & Row , 1982
Buku Teks