Voir la notice de l'article provenant de la source European Digital Mathematics Library
@article{MAN_1967__172_161583, author = {S. Sanatani}, title = {On {Planar} {Group} {Diagrams}}, journal = {Mathematische Annalen}, pages = {203--208}, publisher = {mathdoc}, volume = {172}, year = {1967}, zbl = {0152.41001}, url = {http://geodesic.mathdoc.fr/item/MAN_1967__172_161583/} }
S. Sanatani. On Planar Group Diagrams. Mathematische Annalen, Tome 172 (1967), pp. 203-208. http://geodesic.mathdoc.fr/item/MAN_1967__172_161583/