1. Bowlby J. Attachment and Loss: Vol. 1 : Attachment. Basic Books, New York 1969.
2. Bowlby J. Attachment and Loss: Vol. 2.: Separation: Anxiety and anger. Basic Books, New York 1973.
3. Bowlby J. Attachment and Loss: Vol. 3.: Loss: Sadness and depression. Basic Books, New York 1980.
4. Ainsworth MD, Blehar MC, Waters E.et al. Patterns of attachment : a psychological study of the Strange Situation. Hillsdale, NJ, Lawrence Erlbaum Associates, 1978.
5. Main M, Kaplan N, Cassidy J. Security in infancy, childhood and adulthood: a move to the level to representation. In: Growing points of attachment theory and research. Bretherton I, Waters E eds. Monogr Soc Res Child Dev 1985; 50: 66-104.