1. The first year of life;Spitz,1965
2. Attachment and loss. volume I. attachment;Bowlby,1969
3. Helping relationships: basic concepts for the helping professions;Combs,1973
4. Infants in institutions: a comparison of their development with family-reared infants during the first year of life;Provence,1962
5. Maternal-infant bonding;Klaus,1976