@article{SM_2010_201_2_a0,
     author = {S. M. Ageev and D. Repov\v{s}},
     title = {On extending actions of groups},
     journal = {Sbornik. Mathematics},
     pages = {159--182},
     publisher = {mathdoc},
     volume = {201},
     number = {2},
     year = {2010},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_2010_201_2_a0/}
}