DescriptionDelboeuf.jpg English: Delboeuf illusion Date 29 May 2009 (original upload date) Source Own work (Original text: I created this work entirely
DescriptionDelboeuf 1891.JPG English: Portrait of Belgian Mathematician Joseph Delboeuf Français : Portrait du mathématicien belge Joseph Delboeuf Date 1891
DescriptionMaison-de-Delboeuf-1879-Liege.jpg Français : Maison de Joseph Delboeuf (1879) à Liège, 21, rue Hemricourt English: Joseph Delboeuf's house (1879) in