1. The forced pendulum equation: a paradigm fo rnonlinear analysis and dynamical systems;Mawhin;Expo. Math.,1988
2. Seventy-five years of global analysis around the forced pendulum equation;Mawhin;Proc. EQUADIFF,1997
3. Uber erzwungene schwingungen bei endlichen amplituden;Hamel;Math. Ann.,1922
4. On the use of asymptotics in nonlinear boundary value problems;Dancer;Ann. Mat. Pura Appl.,1982
5. Oscillations forcées de systèmes hamiltoniens;Willem,1981