Wason, Paul K.
Cambridge University Press, 2009
eBooks
Allison, Penelope M.
Routledge, 1999
Buku Teks
edited by Kelley Hays-Gilpin and David S. Whitley
Routledge, 1998
Buku Teks
edited by Marcello A. Canuto and Jason Yaeger
Routledge, 2000
Buku Teks
Little, Barbara J.
Left Coast Press, 2014
Buku Teks