First reponse, best response: my first Medium piece was an autobiographical essay about NYC in 1981. I got the following reply from a man who'd stayed in the same building five years before. He also got to know Jeff, the super-eccentric building superintendent.

"Dear Mark, I am Alain, French, living in Nice, France. During the summer 1976 I was kind of a young musician backpacker tripping in NYC. I don’t remember how but I stayed in Jeff’s home for about 2 weeks. Today I made a search on google about the name Jeff Riedel and I found your text. All you say is extraordinarily exact about this amazing person. So I want to thank you for the help you gave to my memory. All the best. Alain"