Khamaganova EA, Blezer H, McKay A, Ramble C.  2002.  Princes Esper and Dii Ukhtomsky and their Contribution to the Study of Buddhist Culture. Tibet, Past and Present: Tibetan Studies I. PIATS 2000: Tibetan Studies: Proceedings of the Ninth Seminar of the International Association for Tibetan Studies, Leiden 2000. :307-326.