EL-OWAIDY, Hassan. ON PERTURBATIONS OF A CLASS OF SELF-EXCITED OSCILLATORS Periodica Polytechnica Mechanical Engineering, [S. l.], v. 18, n. 1, p. 61–70, 1974. Disponível em: https://pp.bme.hu/me/article/view/5985. Acesso em: 19 may. 2024.