APA (7e ed.) Bronvermelding

Perls, F. S. (1969). Ego, hunger, and aggression; the beginning of gestalt therapy. Random House.

Chicago (17e ed.) Bronvermelding

Perls, Frederick S. Ego, Hunger, and Aggression; the Beginning of Gestalt Therapy. New York: Random House, 1969.

MLA (9e ed.) Bronvermelding

Perls, Frederick S. Ego, Hunger, and Aggression; the Beginning of Gestalt Therapy. Random House, 1969.