Παραπομπή σε μορφή APA (7η εκδ.)

Gruber, H. E., & Piaget, J. (1981). Darwin on man: A psychological study of scientific creativity / Howard E. Gruber. Foreword to the first ed. by Jean Piaget (2. ed.). Univ. of Chicago Press.

Παραπομπή σε μορφή Chicago (17η εκδ.)

Gruber, Howard E., και Jean Piaget. Darwin on Man: A Psychological Study of Scientific Creativity / Howard E. Gruber. Foreword to the First Ed. by Jean Piaget. 2. ed. Chicago: Univ. of Chicago Press, 1981.

Παραπομπή σε μορφή MLA (8th εκδ.)

Gruber, Howard E., και Jean Piaget. Darwin on Man: A Psychological Study of Scientific Creativity / Howard E. Gruber. Foreword to the First Ed. by Jean Piaget. 2. ed. Univ. of Chicago Press, 1981.