Duke University Press,
Majalah, Jurnal, Buletin
University Of Pennsylvania Press,
Majalah, Jurnal, Buletin
Lewis, C.S., author
Harper Trophy, 2000
Buku Teks
edited by Harry R. Warfel, Ralph Gabriel
American Book Company, 1963
Buku Teks
Skolnick, Jerome H., author
Little, Brown, 1985
Buku Teks