Forde, C. Daryll
Methuen , 1956
Buku Teks
Firth, Raymond
The New American Library, 1958
Buku Teks
Spencer, J.E.
John Wiley & Sons, 1969
Buku Teks
Firth, Raymond
Thomas Nelson and Sons, 1947
Buku Teks
Firth, Raymond
Thomas Nelson and Sons, 1950
Buku Teks