Khôi, L. H., Đặng X. Hồng, and N. L. Đống. “Some Problems about Archimedean Triangular Norms”.
Journal of Computer Science and Cybernetics
, vol. 20, no. 4, Aug. 2012, pp. 373-8, doi:10.15625/1813-9663/20/4/1906.