Hồ, Nguyễn Cát, and Lê Xuân Vinh. “On Some Properties of Ordering Relation in Non-Homogeneous Hedge Algebras”. <i>Journal of Computer Science and Cybernetics</i> 19, no. 4 (July 27, 2012): 373–381. Accessed November 5, 2025. https://jcc.vast.vn/jcc/article/view/1546.