@article{SM_2013_204_10_a1,
     author = {A. B. Kupavskii and A. M. Raigorodskii},
     title = {Obstructions to the realization of distance graphs with large chromatic numbers on spheres of small radii},
     journal = {Sbornik. Mathematics},
     pages = {1435--1479},
     year = {2013},
     volume = {204},
     number = {10},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_2013_204_10_a1/}
}