@article{ZNSL_1982_122_a1,
     author = {N. M. Gulevich},
     title = {An estimation of deviation of fixed points from a~nonconvex set},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {13--16},
     publisher = {mathdoc},
     volume = {122},
     year = {1982},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1982_122_a1/}
}