APA (7th ed.) Citation

Walker, C., Speed, E., & Taggart, D. (2018). Our capacity to impact policy. Psychologist, 40.

Chicago Style (17th ed.) Citation

Walker, Carl, Ewen Speed, and Danny Taggart. "Our Capacity to Impact Policy." Psychologist 2018: 40.

MLA (9th ed.) Citation

Walker, Carl, et al. "Our Capacity to Impact Policy." Psychologist, 2018, p. 40.