Andrews, Richard, author
Cambridge University Press, 2009
eBooks
Cambridge University Press, 1993
eBooks
Durant, Will, author
Simon and Schuster, 1953
Buku Teks
Burckhardt, Jacob, author
Harper & Row Publisher, 1958.
Buku Teks
Burckhardt, Jacob, author
Harper Torchbooks, 1968
Buku Teks