Algorithms for Differential Invariants of Symmetry Groups of Differential Equations.

Jeongoo Cheh Peter J. Olver Juha Pohjanpelto Algorithms for Differential Invariants of Symmetry Groups of Differential Equations. 501-532 2008 8 Foundations of Computational Mathematics 4 http://dx.doi.org/10.1007/s10208-005-0206-x db/journals/focm/focm8.html#ChehOP08