TY  - JOUR
AU  - V. V. Lychagin
TI  - Singularities of solutions, spectral sequences, and normal forms of Lie algebras of vector fields
JO  - Izvestiya. Mathematics 
PY  - 1988
SP  - 549
EP  - 575
VL  - 30
IS  - 3
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/IM2_1988_30_3_a5/
LA  - en
ID  - IM2_1988_30_3_a5
ER  -