Plummer, David T.
MacGraw-Hill, 1987
Buku Teks
Onslow, Muriel Wheldale
Cambridge University Press, 2014
Buku Teks
Thomson and Brooks/cole, 2007
Multimedia
Bettelheim, Frederick A.
Harcourt Brace College, 1995
Buku Teks
Morris Hein ...[et.al.]
Brooks/Cole, 1993
Buku Teks