Nonlinear Perturbations

Asymptotic Theory of Hamiltonian and other Systems with all Solutions Nearly Periodic

1962 • 412 citations

A General Perturbation Method for Quantum Mechanical Problems

1966 • 28 citations

General Perturbational Solution of the Harmonically Forced van der Pol Equation

1961 • 12 citations

Motion of a Charged Particle in a Spatially Periodic Magnetic Field

1969 • 4 citations