@article{ZNSL_1974_45_a9,
     author = {V. P. Fedotov},
     title = {Geometric mean of convex sets},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {113--116},
     year = {1974},
     volume = {45},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1974_45_a9/}
}