Non-Local Methods for Pendulum-Like Feedback Systems
0 are already deecribed by I. Newton (116]. However it was 250 years later that F. Tricorni (147] carried out the first non-local qualitative investigation of equation (0.1) with arbitrary o ~ 0 and "'{ ~ 0. It was proved by F. Tricorni that any solution of (0.1) with o > 0 corresponds either to a rotatory motion or to ...