Voir la notice de l'article provenant de la source European Digital Mathematics Library
@article{ELMA_1971__26_141012, author = {H. Hadwiger and R. Schneider}, title = {Ungel\"oste {Probleme.}}, journal = {Elemente der Mathematik}, pages = {58--58}, publisher = {mathdoc}, volume = {26}, year = {1971}, url = {http://geodesic.mathdoc.fr/item/ELMA_1971__26_141012/} }
H. Hadwiger; R. Schneider. Ungelöste Probleme.. Elemente der Mathematik, Tome 26 (1971), p. 58. http://geodesic.mathdoc.fr/item/ELMA_1971__26_141012/