Hasan Hameed, Ahmed, Ekhlas Annon Mousa, Abdulsattar Abdullah hamad, and . . “Upper Limit Superior and Lower Limit Inferior of Soft Sequences”. International Journal of Engineering & Technology 7, no. 4.19 (November 27, 2018): 40–44. Accessed April 28, 2024. https://www.sciencepubco.com/index.php/ijet/article/view/22010.