Ilbert, Courtenay
Oxford University Press , 1947
Buku Teks
Rydon, Joan
Oxford University Press, 1986
Buku Teks
Denny J.A., author
Pustaka Sinar Harapan, 2006
Buku Teks
Baerwald, Hans H.
Cambridge University Press, 1974
Buku Teks
Solomon, David
George Allen & Union, 1978
Buku Teks