Bibliografia
em Inglês
2011 CAMBRIDGE UNIVERSITY PRESS
2011 CAMBRIDGE UNIVERSITY PRESS
2009 CAMBRIDGE UNIVERSITY PRESS
2009 CAMBRIDGE UNIVERSITY PRESS
2006 CAMBRIDGE UNIVERSITY PRESS
2006 CAMBRIDGE UNIVERSITY PRESS
2005 CAMBRIDGE UNIVERSITY PRESS
2004 CAMBRIDGE UNIVERSITY PRESS
1999 PENGUIN LONGMAN PUBLISHING
1999 CAMBRIDGE UNIVERSITY PRESS
1993 Oxford University Press
1985 CAMBRIDGE UNIVERSITY PRESS
2000 Macmillan Education
Alan Maley
