@article{700803,
     title = {O poperechnikakh Urysona $n$-mernoi Evklidovoi sfery},
     booktitle = {General Topology and its Relations to Modern Analysis and Algebra},
     series = {GDML\_Books},
     publisher = {Academia Publishing House of the Czechoslovak Academy of Sciences},
     address = {Praha},
     year = {1972},
     pages = {441-442},
     mrnumber = {MR0358720},
     zbl = {0313.57006},
     url = {http://dml.mathdoc.fr/item/700803}
}

Tikhomirov, V. M.; Tumarkin, L. A. О поперечниках Урысона $n$-мерной Эвклидовой сферы, dans General Topology and its Relations to Modern Analysis and Algebra, GDML_Books,  (1972), pp. 441-442. http://gdmltest.u-ga.fr/item/700803/