@article{RM_1977_32_6_a8,
     author = {V. E. Govorov},
     title = {Associativity formulas},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     year = {1977},
     volume = {32},
     number = {6},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/RM_1977_32_6_a8/}
}