1. G.H. Hardy, Note on a theorem of Hilbert concerning series of positive terms. Proc. Lond. Math. Soc. 23(2), Records of Proc. xlv-xlvi (1925)
2. G.H. Hardy, J.E. Littlewood, G. Pólya, Inequalities (Cambridge University Press, Cambridge, 1934)
3. B.C. Yang, Discrete Hilbert-type inequalities (Bentham Science Publishers, The United Arab Emirates, 2011)
4. Z. Wang, D. Guo, Introduction to special functions (Science Press, Beijing, China, 1979)
5. D.S. Mitrinović, J.E. Pe$$\check {c}$$arić, A.M. Fink, Inequalities involving functions and their integrals and derivatives (Kluwer Acaremic Publishers, Boston, 1991)