"He was born in Kraków and decided to tie his scientific path with this city, although he would be welcome by the most prestigious universities in the world, as evidenced by the twenty-five years of romance with Yale University, where he was a visiting professor. In spite of his age (born in 1928) he does not slow down – he is still working scientifically, he publishes articles."
January 1, 1970
https://en.wikiquote.org/wiki/W%C5%82odzimierz_Ptak