@article{MZM_1996_59_1_a3,
     author = {V. K. Beloshapka},
     title = {Invariants of {CR-manifolds} associated with the tangent quadric},
     journal = {Matemati\v{c}eskie zametki},
     pages = {42--52},
     publisher = {mathdoc},
     volume = {59},
     number = {1},
     year = {1996},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1996_59_1_a3/}
}