D Azagra, EL Gruyer, C Mudarra - arXiv preprint arXiv:1706.02235, 2017 - arxiv.org
Given $ X $ a Hilbert space, $\omega $ a modulus of continuity, $ E $ an arbitrary subset of
$ X $, and functions $ f: E\to\mathbb {R} $, $ G: E\to X $, we provide necessary and sufficient …