Noor Ahmed Shaikh (2025) “APPLICATION OF COMPLEMENTARY BIVARIATIONAL PRINCIPLES TO PERTURBATION THEROTY ”, Sindh University Research Journal - SURJ (Science Series), 25((1&2) 1993 issued Sep). Available at: https://sujo.usindh.edu.pk/index.php/SURJ/article/view/7796 (Accessed: 26June2026).