Who is Elisabeth Kubler-Ross from Necessary Losses and what is their importance?

Elisabeth Kubler-Ross is the author of On Death and Dying. She proposes that there are stages of dying that people go through, and need to go through, to have an appropriate death. In this book, Viorst disagrees with Kubler-Ross, because she feels that everyone does death in his and her own way, and that there is no pat, prescribed method for a good death.