Bhattacharyya, P. K. “Geometrical Ray Tracing of Ion-Trajectories for an Astigmatic Sector Focused Beta Ray Spectrograph”. Defence Science Journal 21, no. 4 (October 1, 2014): 283–290. Accessed August 20, 2025. https://publications.drdo.gov.in/ojs/index.php/dsj/article/view/6293.