Zafar Ali , Jaweria Riaz , Mahwash Rashid. 2012. “Skeletal and Extra Skeletal Ewing’s Sarcoma / Primitive Neuroectodermal Tumors(PNET): Clinicopathological Study”. Journal of Rawalpindi Medical College 16 (2). https://journalrmc.com/index.php/JRMC/article/view/574.