Ekman, P., & Friesen, W. V. (2003). Unmasking the face: A guide to recognizing emotions from facial clues / Paul Ekman and Wallace V. Friesen (4. [print.].). Malor Books.
Cita Chicago (17th ed.)Ekman, Paul, i Wallace V. Friesen. Unmasking the Face: A Guide to Recognizing Emotions from Facial Clues / Paul Ekman and Wallace V. Friesen. 4. [print.]. Cambridge, MA: Malor Books, 2003.
Cita MLA (8th ed.)Ekman, Paul, i Wallace V. Friesen. Unmasking the Face: A Guide to Recognizing Emotions from Facial Clues / Paul Ekman and Wallace V. Friesen. 4. [print.]. Malor Books, 2003.
Atenció: Aquestes cites poden no estar 100% correctes.