Culwin, Fintan
Prentice-Hall, 1998
Buku Teks
Sierra, Kathy
O'Reilly, 2005
Buku Teks
Lambert, Kenneth A.
Course Technology, Cengage Learning, 2012
Buku Teks
Cambridge University Press, 2008
eBooks
by Member of the Summer Institute of Linguistics
University of Sydney, 1958
Buku Teks