Saeed, Muhammad, Hafiz Inam ul Haq, and Mubashir Ali. “Extension of Double Frame Soft Set to Double Frame Hypersoft Set (DFSS to DFHSS)”. HyperSoft Set Methods in Engineering 2 (June 13, 2024): 18–27. Accessed October 25, 2026. https://ojs.sciencesforce.com/index.php/hsse/article/view/293.