Adak, Amal Kumar, and Gauri Kant Kumar. “Pythagorean Fuzzy \((l,u)\)-Level Cuts and Their Applications to Fuzzy Normed Subrings”. Communications in Mathematics and Applications, vol. 16, no. 3, Oct. 2025, pp. 703-16, https://doi.org/10.26713/cma.v16i3.3371.