Florence, P. Sargant
Routledge & Kegan Paul, 1957
Buku Teks
Galbraith, John Kenneth, 1908-2006
Harvard University Press, 1962
Buku Teks
Posner, Richard A.
University od Chicago Press, 1976
Buku Teks SO
edited by Jorg Mahlich and Werner Pascha
Springer, 2012
eBooks
Artikel Jurnal