Read it in English, under the title "Life from Light", co-authored with breatharian chemist Michael Werner. It´s "Living on Light" by Jasmuheen only without channeling and violet light, and much more agreeable to my way of thinking. Werner and Stockli draw on anthroposophical sources as well as the experience of German friends to describe the phenomenon of prnaic nourishment, including his telling of his 10 days under 24-hour medical supervision.