L to R: Dorothy Maud Wrinch, unknown woman in foreground), Élie Cartan (background, head truncated), Andrew Forsyth, Charles Jean de la Vallée Poussin (foreground, holding hat), Eugenio Giuseppe Togliatti (background),Rudolf Fueter, Hermann Weyl; background, partly obscured), at the 1932 International Congress of Mathematicians in Zürich