EVANS, W. D. .; SCHMIDT, K. M. . A Discrete Hardy-Laptev-Weidl-Type Inequality and Associated Schrödinger-Type Operators. Revista Matemática Complutense, v. 22, n. 1, p. 75–90, 11 mar.2009 https://doi.org/10.5209/rev_REMA.2009.v22.n1.16316.