Tilbury, Alex
Cambridge University Press , 2011
Buku Teks
Alex Tilbury, Theresa Clementson, Leslie Hendra, David Rea, Maggie Baigent, Chris Cavey, Nick Robinson ; consultant editor Adrian Doff
Cambridge University Press , 2012
Buku Teks SO
Huddleston, Rodney
Cambridge University Press, 2006
Buku Teks
Ehrlich, Eugene, editor
McGraw-Hill , 2011
Buku Teks SO
Doff, Adrian
Cambridge University Press , 2011
Buku Teks SO