Trevelyan, George Macaulay, 1876-1962, author
Penguin Books, 1986
Buku Teks
Morrison, Herbert, author
Oxford University Press, 1960
Buku Teks
Sun, Zhissheng
New Star Press,
Buku Teks
Lovell, Colin Rhys
Oxford University Press, 1962
Buku Teks
Cressey, Geoge Babcock, author
McGraw-Hill, 1934
Buku Teks