McCarthy, Frederick D.
A Colorgravure , [Date of publication not identified]
Buku Teks SO
Maddex, Robert L.
London: Routledge, 1995,
Buku Referensi
Moore, Russell F.
Littlefield, Adams, 1957
Buku Teks
Finer, S.E.
Clarendon Press Oxford, 1995
Buku Teks
Andrews, William G.
D.van Nostrand Company,Inc., 1968
Buku Teks