APA

Rogerson P., Gilbert J. B., . (1990). Speaking Clearly. New York: cambridge university press.

Chicago

Rogerson Pamela, Gilbert Judy B, . 1990. Speaking Clearly. New York: cambridge university press.

Harvard

Rogerson P., Gilbert J. B., . (1990). Speaking Clearly. New York: cambridge university press.

MLA

Rogerson Pamela, Gilbert Judy B, . Speaking Clearly. New York: cambridge university press. 1990.