Hardy, G. H., Littlewood, J. E., Polya, G., Littlewood, J. E., Polya, G., Littlewood, J. E. 1., . . . Polya, G. (1994). Inequalities (2nd. ed.). Cambridge: Cambridge University Press.

Hardy, G. H., J. E. Littlewood, G. Polya, J. E. Littlewood, G. Polya, John E. 1885-1977 Littlewood, George Po?lya, and George Polya. Inequalities. 2nd. ed. Cambridge: Cambridge University Press, 1994.

Hardy, G. H., et al. Inequalities. 2nd. ed. Cambridge: Cambridge University Press, 1994.