1. Functional analysis and periodic solutions of nonlinear differential equations;Cesari,1963
2. Functional analysis and Galerkin's method;Cesari;Mich. Math. J.,1964
3. Alternative methods in nonlinear analysis;Cesari,1975
4. Nonlinear oscillations in the frame of alternative methods;Cesari,1976
5. Functional analysis, nonlinear differential equations, and the alternative method;Cesari,1976