Goodwin, C. James, author
John Wiley & Sons, 2005
Buku Teks
Shaughnessy, John J., author
McGraw-Hill, 1997
Buku Teks
Shaughnessy, John J., author
McGraw-Hill, 2003
Buku Teks
Dunn, Dana S., author
Wiley-Blackwell, 2009
Buku Teks
Giles, David C., author
Routledge, 2002
Buku Teks