Ordinary and Partial Differential Equations

Exponential behaviour of eigenfunctions and gaps in the essential spectrum.- Laplace integrals in singular differential and difference equations.- Continuation and reflection of solutions to parabolic partial differential equations.- Legendre polynomials and singular differential operators.- Singularities of 3-dimensional potential functions at the vertices and at the edges of the boundary.- Singular perturbations of elliptic boundary value problems.- Singular perturbations of semilinear second order systems.- Higher order necessary conditions in optimal control theory.- Range of nonlinear perturbations of linear operators with an infinite dimensional kernel.- Some classes of integral and integro-differential equations of convolutional type.- Multiparameter periodic differential equations.- Uniform scale functions and the asymptotic expansion of integrals.