Written by a celebrated mathematician and teacher, this text investigates nonlinear differential equations of the second order. Geared toward upper-level undergraduates and graduate students, it opens with an extensive overview of the classical literature and covers point stability, periodic solutions, structural stability, and much more. 1957 edition.
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Finite-Difference Methods for Partial Differential Equations by George E. Forsythe, Wolfgang R. Wasow An interrelated account of difference methods and results, this text covers hyperbolic equations in two independent variables, parabolic and elliptic equations, and initial-value problems in more than two independent variables. 1960 edition.
