Elisabeth Kübler-Ross (July 8, 1926 – August 24, 2004) was a Swiss-American psychiatrist, a pioneer in near-death studies and the author of the groundbreaking book On Death and Dying (1969), where she first discussed her theory of the five stages of grief, also known as the "Kübler-Ross model".She was a 2007 inductee into the National Women's Hall of Fame.
Definition from Wikipedia – Elisabeth Kübler-Ross
The Kübler-Ross model is popularly known as the five stages of grief. Even though it's been represented in modern culture as model of depression, the model was originally designed to postulate a progression of emotional states experienced by terminally ill patients after diagnosis.
Definition from Wikipedia – Kübler-Ross model