Thomas, Hugh, author
Harper & Brothers, 1961
Buku Teks
Preston, Paul, author
Dorsey Press, 1986
Buku Teks
Cattell, David T.
University of California Press, 1957
Buku Teks
Jackson, Gabriel
Princeton University Press, 1972
Buku Teks
Brenan, Gerald
Cambridge University Press, 1993
Buku Teks