@article{MZM_1991_49_3_a18,
     author = {V. S. Balaganskii},
     title = {Weak openness of the metric projection},
     journal = {Matemati\v{c}eskie zametki},
     pages = {135--144},
     publisher = {mathdoc},
     volume = {49},
     number = {3},
     year = {1991},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1991_49_3_a18/}
}