Liu, Cheng-Yu, Huai-Min Wang, and Pan-Chio Tuan. “Input Estimation Algorithms for Reentry Vehicle Trajectory Estimation”. Defence Science Journal 55, no. 4 (October 1, 2005): 361-375. Accessed December 16, 2019. https://publications.drdo.gov.in/ojs/index.php/dsj/article/view/1999.