Clark, Timothy R.
Cambridge University Press, 2011
eBooks
Robbins, Paul, author
Wiley-Blackwell, 2014
Buku Teks
Rubin, Edward S., author
McGraw-Hill, 2001
Buku Teks
Attfield, Robin
Purdue University Press, 1999
Buku Teks
Allen L. Hammond [and others]
Oxford University Press , 1996
Buku Teks