Kolb, Brayn, author
Amazon, 2005
Buku Teks
Sanford, Anthony J., author
[Cambridge University Press, ], 2012
eBooks
Sousa, David A., author
Corwin Sage, 2011
Buku Teks
Grilly, David M., author
Pearson, 2012
Buku Teks
Cameron S. Carter, editor
[, Springer], 2012
eBooks