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@article{DAN_1996_347_3_a2, author = {V. V. Volchkov}, title = {Two-radii theorems on spaces of constant curvature}, journal = {Doklady Akademii Nauk}, pages = {300--302}, publisher = {mathdoc}, volume = {347}, number = {3}, year = {1996}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1996_347_3_a2/} }
V. V. Volchkov. Two-radii theorems on spaces of constant curvature. Doklady Akademii Nauk, Tome 347 (1996) no. 3, pp. 300-302. http://geodesic.mathdoc.fr/item/DAN_1996_347_3_a2/