1. The Psychology of Children's Drawings;Eng,1931
2. Children's drawings of houses;Kerr;Br. J. Med. Psychol.,1937
3. Mental and Scholastic Tests;Burt,1921
4. The smiling response: a contribution to the ontogenesis of social relations;Spitz;Gen. Psychol. Monogr.,1946
5. The visual behaviour of infants in the first few weeks of life;Gough,1962