1. Abraham, K. (1927). Selected papers. London: Hogarth Press and Institute of Psycho-analysis.
2. Akisal, H. S., & McKinney, W. T. (1975). Overview of recent research in depression. Archives of General Psychiatry, 32, 285–305.
3. Bowlby, J. (1961). Process of mourning. International Journal of Psychoanalysis, 42, 317–340.
4. Bowlby, J. (1963a). Pathological mourning and childhood mourning. Journal of the American Psychoanalytic Association, 11, 500–541.
5. Bowlby, J. (1963b). Process of mourning. International Journal of Psychoanalysis, 47, 14–25.