Twentieth century speech and voice correction

MLA

Fröschels, Emil. Twentieth Century Speech and Voice Correction. New York: The Philosphical Library, 1948.

APA

Fröschels, E. (1948). Twentieth century speech and voice correction. New York: The Philosphical Library.

Chicago

Fröschels, Emil, Twentieth Century Speech and Voice Correction. New York: The Philosphical Library, 1948.