Crystal, David, 1941-
Cambridge University Press, 2004
Buku Teks
Crystal, David, 1941-
Cambridge University Press, 2005
Buku Teks
Dalby, Andrew
A. Lane, 2002
Buku Teks
Austin, Peter K., editor
Cambridge University Press, 2011
eBooks
Harris, David P.
McGraw-Hill, 1969
Buku Teks