@article{INTG_1969_2_a0,
     author = {M. A. Akivis},
     title = {Three-webs of multidimensional surfaces},
     journal = {Itogi Nauki i Tekhniki. Seriya Problemy Geometrii. Trudy Geometricheskogo Seminara},
     pages = {7--31},
     publisher = {mathdoc},
     volume = {2},
     year = {1969},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/INTG_1969_2_a0/}
}