Parallelogram inequalities in banach spaces and some properties of a dual mapping
English version (Springer): Ukrainian Mathematical Journal 40 (1988), no. 6, pp 650-652.
Citation Example: Al'ber Ya. I., Notik A. I. Parallelogram inequalities in banach spaces and some properties of a dual mapping // Ukr. Mat. Zh. - 1988. - 40, № 6. - pp. 769-771.
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