Lewis, Oscar, author
Random Hause, 1961
Buku Teks
by Michele Moore [and others]
The Falmer Press, 1996
Buku Teks
Tucker, William P.
University of Minnesota Press, 1958
Buku Teks
Myers, Bernard S., author
Oxford University Press, 956.
Buku Teks
Griffiths, Brian, author
Praeger , 1972
Buku Teks