@article{ZNSL_1979_83_a4,
     author = {V. P. Fedotov},
     title = {Structures generated by invariants},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {83--92},
     year = {1979},
     volume = {83},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1979_83_a4/}
}