@article{107037, author = {Karel Svoboda}, title = {Contribution to the characterization of the sphere in $E^3$}, journal = {Archivum Mathematicum}, volume = {015}, year = {1979}, pages = {171-177}, zbl = {0435.53003}, mrnumber = {562341}, language = {en}, url = {http://dml.mathdoc.fr/item/107037} }
Svoboda, Karel. Contribution to the characterization of the sphere in $E^3$. Archivum Mathematicum, Tome 015 (1979) pp. 171-177. http://gdmltest.u-ga.fr/item/107037/
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