Local Euclidean four-point properties which characterize inner-product spaces
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- by J. E. Valentine and S. G. Wayment PDF
- Proc. Amer. Math. Soc. 50 (1975), 337-343 Request permission
Abstract:
Let $M$ be a complete, convex, externally convex metric space. We show $M$ is an inner-product space if and only if for each point $t$ of $M,M$ contains a sphere ${S_t}$ which has the euclidean queasy, feeble or weak four-point property.References
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Additional Information
- © Copyright 1975 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 50 (1975), 337-343
- MSC: Primary 52A50; Secondary 46C05
- DOI: https://doi.org/10.1090/S0002-9939-1975-0370375-6
- MathSciNet review: 0370375