Voir la notice de l'article provenant de la source European Digital Mathematics Library
@article{ELMA_1994__49_1_141568, author = {Vagn Lundsgaard Hansen}, title = {The {Magic} {World} of {Geometry} - {III.} {The} {Dirac} {String} {Problem.}}, journal = {Elemente der Mathematik}, pages = {149--154}, publisher = {mathdoc}, volume = {49}, number = {1}, year = {1994}, zbl = {0834.57007}, url = {http://geodesic.mathdoc.fr/item/ELMA_1994__49_1_141568/} }
Vagn Lundsgaard Hansen. The Magic World of Geometry - III. The Dirac String Problem.. Elemente der Mathematik, Tome 49 (1994) no. 1, pp. 149-154. http://geodesic.mathdoc.fr/item/ELMA_1994__49_1_141568/