APA (7th ed.) Citation

Day, S., McMahan, E., & Funk, R. (1987). Keeping in touch: Writing clearly. Macmillan.

Chicago Style (17th ed.) Citation

Day, Susan, Elizabeth McMahan, and Robert Funk. Keeping in Touch: Writing Clearly. New York: Macmillan, 1987.

MLA (9th ed.) Citation

Day, Susan, et al. Keeping in Touch: Writing Clearly. Macmillan, 1987.