Blaise, Clark, author
General Publishing, 1974
Buku Teks
Corry, Stephen, author
Freeman Press, 2011
Buku Teks
Rosile, Grace Ann, author
Emerald, 2016
eBooks
Wang, Lv, author
China Renmin University Press, 2015
eBooks
Pieper, Josef, author
Pantheon Books, 1955
Buku Teks