Richetti, John, author
John Wiley & Sons, 2017
Buku Teks
Stephen, Leslie, 1832-1904, author
University Paperbacks, 1963
Buku Teks
Trevelyan, George Macaulay, 1876-1962, author
Longmans, Green, 1951
Buku Teks
Thomson, Thomas, author
Cambridge University Press, 2012
eBooks
Mathias, Peter
Methuen , 1979
Buku Teks