Contributions to the Theory of Nonlinear Oscillations, Volume IV

*Frontmatter, pg. i*Preface, pg. v*Contents, pg. vii*I. On the Non-Linear Difference-Differential Equation y1(t) = [A - By(t-r) ly (t), pg. 1*II. On the Critical Points of a Class of Differential Equations, pg. 19*III. Optimal Discontinuous Forcing Terms, pg. 29*IV. On the Structure of Symmetric Periodic Solutions of Conservative Systems, with Applications, pg. 53*V. Asymptotic Behavior of Solutions of Canonical Systems Near a Closed, Unstable Orbit, pg. 85*VI. Small Periodic Perturbations of an Autonomous System of Vector Equations, pg. 111*VII. Rotated Vector Fields and an Equation for Relaxation Oscillations, pg. 125*VIII. A Survey of Lyapunov's Second Method, pg. 141*IX. On Phase Portraits of Critical Points in n-Space, pg. 167*X. On Non-Linear Repulsive Forces, pg. 201*Backmatter, pg. 214