Soward, F.H., author
Oxford University Press, 1950
Buku Teks
Keirstead, Burton Seely, author
Oxford University Press, 1956
Buku Teks
Rock, Paul, author
Clarendon Press , 1986
Buku Teks
Manzer, Ronald A., author
McGraw-Hill Ryerson, 1974
Buku Teks
Spencer, Robert A., author
Oxford University Press, 1959
Buku Teks