@article{SM_1990_65_2_a1,
     author = {S. A. Antonyan},
     title = {Retraction properties of an orbit space},
     journal = {Sbornik. Mathematics},
     pages = {305--321},
     publisher = {mathdoc},
     volume = {65},
     number = {2},
     year = {1990},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_1990_65_2_a1/}
}