@article{FAA_1975_9_3_a1,
     author = {A. M. Gabri\`elov and I. M. Gel'fand and M. V. Losik},
     title = {Combinatorial calculus of characteristic classes},
     journal = {Funkcionalʹnyj analiz i ego prilo\v{z}eni\^a},
     pages = {5--26},
     publisher = {mathdoc},
     volume = {9},
     number = {3},
     year = {1975},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/FAA_1975_9_3_a1/}
}