Differential Equations

Reduction methods via minimax.- On multiple solutions of nonlinear elliptic equations with odd nonlinearities.- Positive solutions of semilinear elliptic problems.- A regularity theorem for inverse bounded and accretive operators in abstract Hilbert space.- How to remember the Sobolev inequalities.- The adjoint equation of a linear Volterra Stieltjes-integral equation with a linear constraint.- On a fixed point index method for the analysis of the asymptotic behavior and boundary value problems of process and semidynamical systems.- to bifurcation theory.- Sobre estabilidad topologica.- Solvability of operator equations involving nonlinear perturbations of Fredholm mappings of nonnegative index and applications.- Some remarks on a wave equation with a nonlocal interaction.- The mountain pass theorem: Theme and variations.- Optimal spline solutions of systems of ordinary differential equations.- Structurally stable second order differential equations.