Internal working model of attachment
Internal working model of attachment is a psychological approach that attempts to describe the development of mental representations, specifically the worthiness of the self and expectations of others' reactions to the self. This model is a result of interactions with primary caregivers which become internalized, and is therefore an automatic process. John Bowlby implemented this model in his attachment theory in order to explain how infants act in accordance with these mental representations. It is an important aspect of general attachment theory.
Kübler-Ross model
The model was first introduced by Swiss-American psychiatrist Elisabeth Kübler-Ross in her 1969 book "On Death and Dying", and was inspired by her work with terminally ill patients. Motivated by the lack of instruction in medical schools on the subject of death and dying, Kübler-Ross examined death and those faced with it at the University of Chicago medical school. Kübler-Ross' project evolved into a series of seminars which, along with patient interviews and previous research, became the foundation for her book. Although Kübler-Ross is commonly credited with creating stage models, earlier bereavement theorists and clinicians such as Erich Lindemann, Collin Murray Parkes, and John Bowlby used similar models of stages of phases as early as the 1940s.