Nicolas, Joanna, author
McGraw-Hill; Open University Press, 2012
Buku Teks
Gould, Jonathan W., author
Sage, 1998
Buku Teks
Briggs, Freda, author
Allen & Unwin, 1997
Buku Teks
Lawrence, Anne, author
Open University Press, 2004
Buku Teks
Davies, liz, author
Learning Matters Ltd., 2008
Buku Teks