APA (7th ed.) Citation

Ekman, P., Davidson, R. J., & Friesen, W. V. (1990). The Duchenne smile: Emotional expression and brain physiology. II. Journal of personality and social psychology, 58(2), 342. https://doi.org/10.1037/0022-3514.58.2.342

Chicago Style (17th ed.) Citation

Ekman, P., R J. Davidson, and W V. Friesen. "The Duchenne Smile: Emotional Expression and Brain Physiology. II." Journal of Personality and Social Psychology 58, no. 2 (1990): 342. https://doi.org/10.1037/0022-3514.58.2.342.

MLA (9th ed.) Citation

Ekman, P., et al. "The Duchenne Smile: Emotional Expression and Brain Physiology. II." Journal of Personality and Social Psychology, vol. 58, no. 2, 1990, p. 342, https://doi.org/10.1037/0022-3514.58.2.342.