edited by Victor A. Hauser
Oxford University Press, 1986
Buku Teks
Clegg, H. A., author
Clarendon Press, 1964
Buku Teks
Trevelyan, George Macaulay, 1876-1962, author
Longmans, Green, 1945
Buku Teks
Babington, Anthony
Routledge , 1991
Buku Teks
Thomas, D.R.
Stevens & Sons, 1980
Buku Teks