Descriptors
Solvability of planar complex linear vector fileds , Classification of vector fields , Classification of vector fields , Linear coefficients , Complex-valued continuous function , Invariant K (π) , Hypoellipticity , Ellipticity , Local solvability conditions in R2\ {0} , Solvability in the classes (NO-E) , Vector field elliptic in R2\ {0} , Vector field hypoelliptic but not elliptic in R2\ {0} , Preparatory reductions
