Second Order Differential Equations presents a classical piece of theory concerning hypergeometric special functions as solutions of second-order linear differe

This volume is intended as an essentially self contained exposition of portions of the theory of second order quasilinear elliptic partial differential equation

Second order linear parabolic and elliptic equations arise frequently in mathematics and other disciplines. For example parabolic equations are to be found in s

This memoir presents machinery for analyzing many discrete physical situations, and should be of interest to physicists, engineers, and mathematicians. We devel

The inverse problem of the calculus of variations was first studied by Helmholtz in 1887 and it is entirely solved for the differential operators, but only a fe