The Oral History of Tibetan Studies project at Oxford, initiated by Rachael Griffiths, is an incredible resource (https://oralhistory.iats.info/); if you wish you can now listen to an interview with Ernst Steinkellner for nearly four (!) hours: https://www.youtube.com/watch?v=xx7qNu2J4XA -- one of altogether 89 interviews that were conducted so far.