Ochs, Ginger Murphy
Appleton & Lange , 1997
Buku Teks
Khan, M. Gabriel, author
Saunders , 2003
Buku Teks
Brenna H. Mayer, editor
Springhouse, 2002
Buku Teks
editors, Adam Gacek, Witold Pedrycz
Springer, 2012
eBooks
Attridge, Derek, author
Longman, 1982
Buku Teks