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2. Hardy, G. H., Littlewood, J. E. and Polya, G.Inequalities, Cambridge University Press, 1964.
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4. Singh, S. K. and SreenivasuluRevue de la Faculté des Sciences de l’université d’Istanbul, Serie A, 1965,30, 71–75; Corrigendum,Ibid., 1965,30, 101–102.