Matthews, Janice R.
Cambridge University Press, 2016
Buku Teks SO
Welty, Gordon
Woodhead Publishing, 2013
Buku Teks SO
Leith, John D.
Burgess, 1970
Buku Teks SO
Geller, Yu A.
MIR Publishers, 1977
Buku Teks SO
Kalvelage, Carl
Foresman, 1976
Buku Teks SO