Murphy, R. (2007). Essential grammar in use: A self-study reference and practice book for elementary students of english with answers (3rd ed.). Cambridge University.
Cita Chicago (17th ed.)Murphy, Raymond. Essential Grammar in Use: A Self-study Reference and Practice Book for Elementary Students of English with Answers. 3rd ed. Cambridge: Cambridge University, 2007.
Cita MLA (9th ed.)Murphy, Raymond. Essential Grammar in Use: A Self-study Reference and Practice Book for Elementary Students of English with Answers. 3rd ed. Cambridge University, 2007.
Atenció: Aquestes cites poden no estar 100% correctes.