@article{VMUMM_2008_3_a3,
     author = {P. A. Borodin},
     title = {Convexity of $2${-Chebyshev} sets in {Hilbert} space},
     journal = {Vestnik Moskovskogo universiteta. Matematika, mehanika},
     pages = {16--19},
     publisher = {mathdoc},
     number = {3},
     year = {2008},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VMUMM_2008_3_a3/}
}