Applications of a simplified bilinear method to ion-acoustic solitary waves in plasma Fadi Awawdeh, H.M. Jaradat and S. Al-Shara’ Eur. Phys. J. D, 66 2 (2012) 40 Published online: 24 February 2012 DOI: 10.1140/epjd/e2011-20518-0