At Yale, among others, he collaborated with Włodzimierz Ptak, who recalled Gershon as a true friend and one of the most intellectually related and valued people.[2]
^Bętkowska, Teresa (August–September 2010). "Mistrz niszowej dyscypliny"(PDF). Alma Mater (in Polish) (126–127). Kraków: 41–46. Archived from the original(PDF) on 2016-03-05.