Ekman, P. Expression and the nature of emotion: Paul Ekman. Approaches to emotion.(c 1984).
Chicago-viite (17. p.)Ekman, Paul. "Expression and the Nature of Emotion: Paul Ekman." Approaches to Emotion.(c 1984) .
MLA-viite (8. p.)Ekman, Paul. "Expression and the Nature of Emotion: Paul Ekman." Approaches to Emotion.(c 1984), .
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.