edited by Douglas McConatha, Christian Penny, Jordan Schugar, and David Bolton
Igi Global, 2014
Buku Teks
Nagel, Michael C., author
Oxford University Press, 2016
Buku Teks
edited by Douglas A. Grouws
Macmillan Library Reference, 1992
Buku Referensi
edited by Michael Byram
Routledge, 2000 ; 2004
Buku Referensi
Cook, Vivian, author
ARNOLD, 2001
Buku Teks