edited by Mike Hayhoe and Stephen Parker
Open University Press, 1994
Buku Teks
Forer, Lois G.
Norton, 1984
Buku Teks
Clyde, Paul Hibbert
Prentice-Hall, 1953
Buku Teks
Walker, Allan S.
Australian War Memorial, 1956
Buku Teks
Thompson, Warren S.
The University of Chicago Press, 1959
Buku Teks