Gray, Richard, 1944-, author
Longman, 1991
Buku Teks
Stepanchev, Stephen, author
Harper and Row, 1965
Buku Teks
Dongguk University Press, 1987
Buku Teks
Currey, R.N.
Oxford University Press, 1946
Buku Teks
Forrest-Thomson, Veronica, author
Manchester University Press, 1978
Buku Teks