Simpson, Sally S.
Cambridge University Press, 2002
Buku Teks
Lawrence M. Salinger, editor
Sage Reference, 2013
Buku Referensi
Sahetapy, J.E.
Eresco, 1994
Buku Teks
H. Setiyono
Bayumedia Publishing, 2005
Buku Teks
general editors, Robert Goldspink and Jeremy Cole
Sweet & Maxwell, 2002
Buku Teks