Marckwardt, A. H. (1958). American English. Oxford University Press.
Cita Chicago (17th ed.)Marckwardt, Albert Henry. American English. New York: Oxford University Press, 1958.
Cita MLA (9th ed.)Marckwardt, Albert Henry. American English. Oxford University Press, 1958.
Atenció: Aquestes cites poden no estar 100% correctes.