Cita APA (7th ed.)
Gray, L. H. (1950). Foundations of language (Second printing.). Macmillan.
Cita Chicago (17th ed.)
Gray, Louis H. Foundations of Language. Second printing. New York: Macmillan, 1950.
Cita MLA (9th ed.)
Gray, Louis H. Foundations of Language. Second printing. Macmillan, 1950.
Atenció: Aquestes cites poden no estar 100% correctes.