Stockwin, J.A.A., author
W.W. Norton, 1982
Buku Teks
Stockwin, J.A.A., author
Weidenfeld and Nicolson, 1975
Buku Teks
Grant, Wyn, author
Harvester Wheatsheaf , 1993
Buku Teks
edited by Harold F. Williamson
Prentice-Hall, 1951
Buku Teks
Baer, Werner, author
Frederick A. Praeger, 1995
Buku Teks