1. Functional analysis and nonlinear differential equations;Cesari,1976
2. Applications of generic bifurcation. I.;Chow;Arch. Rational Mech. Anal.,1975
3. Theory of Ordinary Differential Equations;Cole,1968
4. Foundations of Modern Analysis;Dieudonne,1960
5. Subharmonic and ultraharmonic solutions for weakly non-linear systems;Gambill;J. Rational Mech. Anal.,1956