The Wisdom of Oz – Reflections of a Jungian Sandplay Therapist. Found by way of Schuyler who, when she lived in Japan, lived next to a woman who worked with L. Frank Baum’s great-granddaughter. Apparently her mother’s name was Ozma. She was writing a book at the time about the psychology of Oz and this is it.
There’s a six unit course as well.