Awan, Maj Muhammad Younus, and Irfan Shukr. “METASTATIC HAEMANGIOPERICYTOMA: A RARE VARIETY OF SOFT TISSUE SARCOMA PRIMARILY INVOLVING THE LEFT GLUTEAL MUSCLES: Metastatic Haemangiopericytoma”. Pakistan Armed Forces Medical Journal, vol. 62, no. 4, Dec. 2012, pp. 621-3, https://pafmj.org/PAFMJ/article/view/2036.