Keith, Arthur Berriedale, 1879-1944, author
Watts & Co., 1947
Buku Teks
edited by Amos Rapoport
Angus and Robertson , 1972
Buku Teks
Bartholomew, David J., author
John Wiley & Sons, 1982
Buku Teks
Richard D. Irwin, 1961
Buku Teks
Canter, David
Buku Teks