Hill, John W., author
Pearson Prentice Hall, 2007
Buku Teks
Hill, John W., author
Burgess, 1972
Buku Teks
Cambridge University Press, 2019
eBooks
edited by E.R. Hughes
J.M. Dent & Sons, 1954
Buku Teks
edited by Felipe Fernandez-Armesto
Times Books, 1994
Buku Referensi