Non-holonomic Ideals in the Plane and Absolute Factoring (2008)
We study {\it non-holonomic} overideals of a left differential ideal $J\subset F[\partial_x, \partial_y]$ in two variables where $F$ is a differentially closed field of characteristic zero. The main...
Factoring systems of linear PDEs with finite-dimensional solution space (2003)
Li, Z., Schwarz, F., Tsarev, S.
A D-finite system is a finite set of linear homogeneous partial differential equations in several independent and dependent variables, whose solution space is of finite dimension. Let L be a D-finite...