@article{DAN_1960_134_4_a2,
     author = {R. M. Geidel'man},
     title = {Conformal theory of two-parameter families of spheres},
     journal = {Doklady Akademii Nauk},
     pages = {753--756},
     publisher = {mathdoc},
     volume = {134},
     number = {4},
     year = {1960},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1960_134_4_a2/}
}