edited by Peter Moore, R.J. Berry and A. Hallam
Grolier International, 1993
Buku Referensi
Louw, Gideon N.
Longman Scientific and Technical, 1993
Buku Teks
Macfadyen, A.
Pitman, 1963
Buku Teks
Pandey, B.N.
Tata McGraw-Hill, 2012
Buku Teks
Goater, Timothy M., 1959-
Cambridge University Press, 2014
Buku Teks