Powers, D. G. (1951). Fundamentals of speech. McGraw-Hill.
Cita Chicago (17th ed.)Powers, David Guy. Fundamentals of Speech. New York: McGraw-Hill, 1951.
Cita MLA (9th ed.)Powers, David Guy. Fundamentals of Speech. McGraw-Hill, 1951.
Atenció: Aquestes cites poden no estar 100% correctes.