White, Ron, author
Prentice Hall International English Language Teaching , 1994
Buku Teks
Murray, Maggie, author
Oxford University Press, 1994
Buku Teks
Dixson, Robert J., author
Regents Publishing, 1971
Buku Teks
Ferrer, Jami
Random House, 1985
Buku Teks
Wegmann, Brenda
Random House, 1985
Buku Teks