1. Attachment and dependency: A comparison, attachment and dependency;Ainsworth,1972
2. The concept of a critical period for the development of social responsiveness in early human infancy;Ambrose,1963
3. Relationships between infants' social behavior and their mothers' behavior;Beckwith;Child Development,1972
4. Infant crying and maternal responsiveness;Bell;Child Development,1972
5. Kinesics and context. Essays on body motion communication;Birdwhistell,1970