Forrest, Thomas, author
Oxford University Press, 1969
Buku Teks
Robson, R.W., author
Pacific Publications PTY, 1954
Buku Teks
Mitchell, William E., author
W.W. Norton, 1978
Buku Teks
Wilson, Lindsay
McGraw-Hill , 1975
Buku Teks
Mytinger, Caroline
Macmillan, 1946
Buku Teks