Partial Differential Equns II - Elements of the Classical Theory [Eqns w Constant Coefficients] - Y. Egorov, M. Shubin (Springer, 1995)

Progress in Nonlinear Differential Equations and Applications - T. Cazenave, et al., (Birkhauser, 2006)

Robinson - An Introduction to Ordinary Differential Equations

Tung - Partial Differential Equations And Fourier Analysis, An Introduction