Foers, E.
Oxford University Press, 1957
Buku Teks
edited by Gareth Williams, Martin Kenyon and Lynn Williams
Overseas Student Trust, 1987
Buku Referensi
Stanford, David R.
London, Sweet & Maxwell Limited
Buku Teks
Fink, Stephen L.
Irwin, 1983
Buku Teks
Higher School Pub. House, 1966
Buku Teks