## Abstract

Considering a metric space and its Lipschitz dual one defines the notion of M-ideal and HB-subspace of a metric space (with respect to its Lipschitz dual). One obtain some results analogous to these in the theory of M-ideal and HB-subspaces in a normed space. The results in the paper are based on an extension theorem of McShane [2], [3] and on a uniquenese theorem which is similar to one of R.R.Phelps [10], [11].

## Authors

**Costica Mustata**

“Tiberiu Popoviciu” Institute of Numerical Analysis, Romanian Academy, Romania

## Keywords

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## Paper coordinates

C. Mustăţa, *M-ideals in metric spaces*, ”Babeş-Bolyai” University, Faculty of Math. and Physics, Research Seminars, Seminar on Mathematica Analysis, Preprint Nr.7 (1988), 67-74 (MR # 90b: 54019)

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MR # 90b: 54019

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