@article{MAT_1962_6_1_a0,
     author = {D. Kan},
     title = {A combinatorial definition of homotopy groups},
     journal = {Matematika},
     pages = {3--32},
     publisher = {mathdoc},
     volume = {6},
     number = {1},
     year = {1962},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MAT_1962_6_1_a0/}
}