Thomas Y. Crowell, 1972
Buku Teks
Ferguson, Wallace K.
Sir Isaac Pitman & Sons, [date of publication not identified]
Buku Teks
Whitmarsh, W. F. H.
Longmans, Green and Co., 1960
Buku Teks
Naidis, Mark
Dryden Press, 1972
Buku Teks
Webster, Hutton
D.C. Heath, 1947
Buku Teks