Definition of field through 1960, emphasizing work of Poincaré, Liapounoff, Painlevé, and Goursat. 137 problems.

topics covered include differential equations of the first order, the Riccati equation and existence theorems, second order equations, elliptic integrals and functions, the technique of continuous analysical continuation, the phenomena of the phase plane, nonlinear mechanics, nonlinear integral equations, problems from the calculus of variations and more. 1960 ed. 137 problems.