I was Greg's "suite mate" at Harvard during the 1974-1975 academic year. We spent a couple of Sundays rock-climbing at Quincy Quarry. We remained friends and shared an apartment with two other Harvard classmates for a few months after graduation. I was the one fortunate enough to receive the call from Stanford about his acceptance to the PhD program and pass the information on to a joyful Greg. I'm very sorry to hear of his passing.

I spoke with Greg back in '08, he seemed interested in giving back to the community his best effort to spread defacto academic language, Modula-3, his brilliance to merit their hardwork in that with his colleagues was itself admirable, even when we sometimes try to avoid mention them much. Hope to greet you again Mr Nelson. From Colombia