Goetgheluck, P. “ On a Schur-Type Inequality in \(L^2\)”. Rev. Anal. Numér. Théor. Approx. 21, no. 1 (February 1, 1992): 37–41. Accessed September 3, 2025. https://www.ictp.acad.ro/jnaat/journal/article/view/1992-vol21-no1-art5.