Partial differential equations invariant under conformal or projective transformations. (English) Zbl 0298.35018

Contribut. to Analysis, Collect. of Papers dedicated to Lipman Bers, 245-272 (1974).


35J25 Boundary value problems for second-order elliptic equations
35G05 Linear higher-order PDEs
35B45 A priori estimates in context of PDEs
35J15 Second-order elliptic equations
53A55 Differential invariants (local theory), geometric objects
53B20 Local Riemannian geometry