%0 Journal Article %A Philippe Tondeur %A Lieven Vanhecke %T Isometric Reflections with Respect to Submanifolds and the Ricci Operator of Geodesic Spheres. %J Monatshefte für Mathematik %D 1989 %P 211-218 %V 108 %N 2-3 %I mathdoc %U http://geodesic.mathdoc.fr/item/MOMA_1989__108_2-3_178446/ %F MOMA_1989__108_2-3_178446