Cita APA (7th ed.)

Gower, R. (2006). Grammar in practice 6 (First edition.). Cambridge University Press.

Cita Chicago (17th ed.)

Gower, Roger. Grammar in Practice 6. First edition. Cambridge: Cambridge University Press, 2006.

Cita MLA (9th ed.)

Gower, Roger. Grammar in Practice 6. First edition. Cambridge University Press, 2006.