Ruthven, K.K.
Cambridge University Press, 1979
Buku Teks
Williams III, Frank P.
Pearson , 2014
Buku Teks
McLaughlin, Eugene
Sage, 2013
Buku Teks
Dan S. Felsenthal, Moshe Machover, editors
[Springer, Springer], 2012
eBooks
Hjelle, Larry A.
McGraw-Hill, 1981
Buku Teks