Über die Menge erster Integrale gewisser partieller Differetialgleichungen erster Ordnung
Über ein System partieller Differentialgleichungen und einen zugehörigen Bergman-Operator.
Ueber die Jacobi-Hamilton'sche Integrationsmethode der partiellen Differentialgleichungen erster Ordnung
Unexpected solutions of first and second order partial differential equations.
Unicité pour certains problèmes de Cauchy non-linéaires, complexes, du premier ordre
Unicité pour les équations non linéaires du premier ordre
Uniqueness and approximation of Solutions of first order non linear equations.
Uniqueness and Nonuniqueness for Nonsmooth Divergence Free Transport
Uniqueness and weak stability for multi-dimensional transport equations with one-sided Lipschitz coefficient
The Cauchy problem for a multidimensional linear transport equation with discontinuous coefficient is investigated. Provided the coefficient satisfies a one-sided Lipschitz condition, existence, uniqueness and weak stability of solutions are obtained for either the conservative backward problem or the advective forward problem by duality. Specific uniqueness criteria are introduced for the backward conservation equation since weak solutions are not unique. A main point is the introduction of a generalized...