Mair, L. P.
Christophers, 1948
Buku Teks
Barrett, Charles, author
William Heinemann, 1954
Buku Teks
Sydney University Press, 1974
Buku Teks
Reader's Digest Association.
Reader's Digest Association, 1968
Buku Referensi
Woolford, Donald Mark, author
University of Queensland Press, 1976
Buku Teks