Azad, K. K., and Gunjan Agrawal. “On Hausdorff Extensions and Hausdorff Absolutes of an Orbit Space”. The Journal of the Indian Mathematical Society 60, no. 1-4 (December 1, 1994): 135–143. Accessed May 5, 2024. http://informaticsjournals.com/index.php/jims/article/view/21950.