Cita APA (7a ed.)

Hornby, A. Oxford progressive english for adult Learners. Oxford University Press.

Cita Chicago Style (17a ed.)

Hornby, A.S. Oxford Progressive English for Adult Learners. London: Oxford University Press.

Cita MLA (9a ed.)

Hornby, A.S. Oxford Progressive English for Adult Learners. Oxford University Press.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.