Oscillations 30 Oscillators, Electric 10 Nonlinear oscillations 6 Frequencies of oscillating systems 5 Differential equations, Nonlinear 4 Electric waves 3 Electronic circuits 3 Measurement 3 Nonlinear theories 3 Oscillators, Microwave 3 Vibration 3 Asymptotic expansions 2 Congresses 2 Differential equations 2 Diodes, Semiconductor 2 Electromechanical analogies 2 Hydrofoils 2 Nonlinear mechanics 2 Numerical solutions 2 Oscillators, Crystal 2 Oscillators, Vacuum-tube 2 Radio 2 Southern oscillation 2 Waves 2 Acoustic surface wave devices 1 Almost periodic functions 1 Amplifiers (Electronics) 1 Antennas 1 Approximation theory 1 Asymptotes 1