"Don S." is Don Senzig, one of the founding members of the Wisconsin Computer Society, which had its first meeting on a cold Saturday afternoon in January, 1976. AFAIK, there are still monthly meetings, though it is down to a dozen or so folks that have known each other now for over thirty years. I try to make it to them when I'm out there. Don was a close friend, and is missed. He and Dorothy hosted the meetings at their house for many, many years.