Harrison, M. (2009). Oxford living grammar: Pre-intermediate. Oxford University Press.
Cita Chicago (17th ed.)Harrison, Mark. Oxford Living Grammar: Pre-intermediate. New York: Oxford University Press, 2009.
Cita MLA (9th ed.)Harrison, Mark. Oxford Living Grammar: Pre-intermediate. Oxford University Press, 2009.
Atenció: Aquestes cites poden no estar 100% correctes.