Entire Solutions of a Class of Even Order Quasilinear Elliptic Equations.
Équations aux dérivées partielles sur les groupes de Lie nilpotents
Equivalence and new exact solutions to the Black Scholes and diffusion equations.
Equivalence transformations of the Clebsch equations.
Estimates for derivatives of the Green functions on homogeneous manifolds of negative curvature.
Existence and construction of Vessiot connections.
Exponential law in the jet bundle, symmetries of differential equations and Cartan's moving frame. (Loi exponentielle dans le fibré des jets, symétries des équations différentielles et repère mobile de Cartan.)