Cita APA (7th ed.)

Gilbert, J. B. (1993). Clear speech: Pronunciation and listening comprehension in North American english, student's book (2a. ed.). Cambridge University Press.

Cita Chicago (17th ed.)

Gilbert, Judy B. Clear Speech: Pronunciation and Listening Comprehension in North American English, Student's Book. 2a. ed. Nueva York: Cambridge University Press, 1993.

Cita MLA (9th ed.)

Gilbert, Judy B. Clear Speech: Pronunciation and Listening Comprehension in North American English, Student's Book. 2a. ed. Cambridge University Press, 1993.