Sultana, M., and M. Khalid. “FORMATION OF LOPSIDED AND BAR STRUCTURES IN NON-STATIONARY GRAVITATING SYSTEMS. I- ISOTROPIC CASE”. The Nucleus 50, no. 3 (September 16, 2013): 285–288. Accessed April 19, 2024. http://www.thenucleuspak.org.pk/index.php/Nucleus/article/view/757.