My collected autographs, are they valid signatures? (5.2022) I have the autographs of the late Kristen Nygaard and Ole-Johan Dahl plus the living C. A. R. (Tony) Hoare, Alan Kay and Bjarne Stroustrup. I collected these by approaching the persons at Simula-67’s 25 years anniversary at the University of Oslo (in 1992). In addition, I have a label from a letter to me, signed Per Brinch Hansen. He is also deceased. This most probably is his signature.
