On the afterlife of things in artworks Doris Salcedo's "Atrabiliarios" and other contact relics : the twenty-first Horst Gerson Lecture held in memory of Horst Gerson (1907-1978) in the Aula of the University of Groningen on the 12th of October 2023 - Wagner, Monika 1944- (Gerson lecture, 2023)