Adams, James E., author
Wiley-Blackwell, 2009
Buku Teks
Banks, J. A.
Routledge & Kegan Paul Limited, 1954
Buku Teks
Cannadine, David
Papermac, 1996
Buku Teks
Greene, Donald Johnson, author
Kennikat Press, 1960
Buku Teks
Briggs, Asa
Longman, 1974
Buku Teks