Gray, Richard, 1944-, author
Longman, 1991
Buku Teks
Bogan, Louise, author
Henry Regnery, 1951
Buku Teks
Basic Books, Inc., 1966
Buku Teks
Dembo, L.S., author
University of California Press, 1966
Buku Teks
Falci, Eric, author
Cambridge University Press, 2015
Buku Teks