I. HUSSAIN, F. R. ABRO, A.A. MEMON, and I.A. MEMON. “Multiple Model Based Real Time Estimation of Wheel-Rail Contact Conditions”. Sindh University Research Journal - SURJ (Science Series), vol. 44, no. 4, Dec. 2012, https://sujo.usindh.edu.pk/index.php/SURJ/article/view/5956.