Leach, P. Babyhood: Infant development from birth to two years. Penguin Books.
Chicago-referens (17:e uppl.)Leach, Penelope. Babyhood: Infant Development from Birth to Two Years. Harmondsworth: Penguin Books.
MLA-referens (9:e uppl.)Leach, Penelope. Babyhood: Infant Development from Birth to Two Years. Penguin Books.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.