@article{IM2_2007_71_6_a4,
     author = {V. E. Nazaikinskii and A. Yu. Savin and B. Yu. Sternin},
     title = {Homotopy classification of~elliptic~operators on stratified manifolds},
     journal = {Izvestiya. Mathematics },
     pages = {1167--1192},
     publisher = {mathdoc},
     volume = {71},
     number = {6},
     year = {2007},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_2007_71_6_a4/}
}