Beard, Ruth Mary. An outline of Piaget's developmental psychology for students and teachers / by Ruth M. Beard. - New York : Basic Books, [1969]. - 158 p. ; 22 cm. - 155.4 . Bibliography: p. 123-128. Subjects--Personal Names: Piaget, Jean, 1896-1980. Subjects--Topical Terms: Child psychology. Dewey Class. No.: 155.4