An atlas of infant behavior: A systematic delineation of the forms and early growth of human behavior patterns... illustrated with 3,200 action photographs. Vol. l: Normative series, in collaboration with Helen Thompson and Catherine S. Amatruda. Selected bibliographies (p. 45). Vol. 2: Naturalistic series, in collaboration with Alice V. Keliher, Frances L. Ilg, and Jessie J. Carlson. (2 vols.)

Gesell, who originated the Child Study Center at Yale University, was the founder of the study of child development in the United States. He is best known for his groundbreaking studies of normal child development: beginning in the 1920s, he used advanced cinematic and photographic techniques, including one-way mirrors, to record developmental milestones from infancy to adolescence. His most famous work is the Atlas of Infant Behavior, which contains 3200 photographs documenting the human infant's "visible manifestations of his maturing patterns of action and reaction. . . . Through systematic, pictorial charting, we trust that this Atlas will reveal the patterned organization of the moments and of the developmental sequences of infant behavior" (p. 11).