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.
警告：这些引文格式不一定是100％准确.