APA (7th ed.) Citation

Zook, C., Alcock, R., MacDonald, G., & Decker, D. (2016). letters & emails. Earth Island Journal, 30(4), 3.

Chicago Style (17th ed.) Citation

Zook, Caryl, Robert Alcock, George MacDonald, and Don Decker. "Letters & Emails." Earth Island Journal 30, no. 4 (2016): 3.

MLA (9th ed.) Citation

Zook, Caryl, et al. "Letters & Emails." Earth Island Journal, vol. 30, no. 4, 2016, p. 3.