Riandani PE, Bakar NN, Helmi MR. BEBERAPA SIFAT DARI SUBGRUP FUZZY. Jurnal Matematika UNAND [Internet]. 2016 Mar. 1 [cited 2026 Nov. 4];5(1):57-64. Available from: https://jmua.fmipa.unand.ac.id/index.php/jmua/article/view/201