S. A. El-Serafi

Stability and primary simultaneous resonance of harmonically excited non-linear spring pendulum system

M. Eissa, M. Sayed, S. A. El-Serafi, 2003, Appl. Math. Comput..

Comparison between passive and active control of a non-linear dynamical system

S. A. El-Serafi, H. M. El-Sherbiny, M. H. Eissa, 2006 .