Ali, Amjad, and Atta ur Rehman. “Classification of Cylindrically Symmetric Marder Type Spacetimes According to Their Proper Homothetic Vector Fields”. International Journal of Sciences: Basic and Applied Research (IJSBAR) 25, no. 3 (February 26, 2016): 13–19. Accessed May 3, 2024. https://gssrr.org/index.php/JournalOfBasicAndApplied/article/view/5247.