@article{SM_1983_46_2_a4,
     author = {A. Yu. Ol'shanskii},
     title = {On the {Novikov--Adyan} theorem},
     journal = {Sbornik. Mathematics},
     pages = {203--236},
     publisher = {mathdoc},
     volume = {46},
     number = {2},
     year = {1983},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_1983_46_2_a4/}
}