Mellersh, H.E.L., author
Simon & Schuster, 1994
Buku Referensi
Malek, Jaromir, author
Andre Deutsch, 2010
Buku Referensi
Southgate, Beverley
Routledge , 1996
Buku Teks
Damon, Philip
University of California Press, 1961
Buku Klasik
Rock, Joseph F.
Harvard University Press, 1947
Buku Teks