Cita APA (7th ed.)

Naylor, H., & Murphy, R. (2007). Essential Grammar in use suplementary exercises, with answers (2a. ed.). Cambridge University Press.

Cita Chicago (17th ed.)

Naylor, Helen, i Raymond Murphy. Essential Grammar in Use Suplementary Exercises, with Answers. 2a. ed. Cambridge University Press, 2007.

Cita MLA (9th ed.)

Naylor, Helen, i Raymond Murphy. Essential Grammar in Use Suplementary Exercises, with Answers. 2a. ed. Cambridge University Press, 2007.