Sơn TT, Thái LQ, Nam NV. Hedge algebras and problems of fuzzy ranking Vietnamese documents. J. Comput. Sci. Cybern. [Internet]. 2012 Jul. 10 [cited 2025 Apr. 13];24(1):87-96. Available from: https://vjs.ac.vn/index.php/jcc/article/view/1231