Cita APA (7th ed.)

Rogerson, P., & Gilbert, J. B. (1993). Speaking clearly: Pronunciation and listening comprehension for learners of English, student's book. Cambridge University Press.

Cita Chicago (17th ed.)

Rogerson, Pamela, i Judy B. Gilbert. Speaking Clearly: Pronunciation and Listening Comprehension for Learners of English, Student's Book. Cambridge, Eng: Cambridge University Press, 1993.

Cita MLA (9th ed.)

Rogerson, Pamela, i Judy B. Gilbert. Speaking Clearly: Pronunciation and Listening Comprehension for Learners of English, Student's Book. Cambridge University Press, 1993.