BANERJEE , Abhijit, and Sujoy MAJUMDER. “Some Results on a Question of Li, Yi and Li”. Studia Universitatis Babeș-Bolyai Mathematica 64, no. 3 (September 30, 2019): 367–385. Accessed February 5, 2025. https://studia.reviste.ubbcluj.ro/index.php/subbmathematica/article/view/2309.