Cita APA (7th ed.)

Ekman, P., & Friesen, W. V. (1975). Unmasking the face: A guide to recognizing emotions from facial clues. Prentice-Hall.

Cita Chicago (17th ed.)

Ekman, Paul, i Wallace V. Friesen. Unmasking the Face: A Guide to Recognizing Emotions from Facial Clues. Englewood Cliffs, N.J.: Prentice-Hall, 1975.

Cita MLA (8th ed.)

Ekman, Paul, i Wallace V. Friesen. Unmasking the Face: A Guide to Recognizing Emotions from Facial Clues. Prentice-Hall, 1975.