Rizvi, Vaqar Ahmed. “’UMAR KHAYYĀM AS A GEOMETRICIAN—A SURVEY”. Islamic Studies 24, no. 02 (June 30, 1985): 193–204. Accessed December 6, 2025. http://irigs.iiu.edu.pk:64447/ojs/index.php/islamicstudies/article/view/5844.