Geodesic
Finite-codimensional Chebyshev subspaces in the complex space $C(Q)$
Matematičeskie zametki, Tome 62 (1997) no. 2, pp. 178-191 
L. P. Vlasov. Finite-codimensional Chebyshev subspaces in the complex space $C(Q)$. Matematičeskie zametki, Tome 62 (1997) no. 2, pp. 178-191. http://geodesic.mathdoc.fr/item/MZM_1997_62_2_a2/
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     author = {L. P. Vlasov},
     title = {Finite-codimensional {Chebyshev} subspaces in the complex space $C(Q)$},
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     year = {1997},
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     url = {http://geodesic.mathdoc.fr/item/MZM_1997_62_2_a2/}
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Voir la notice de l'article provenant de la source Math-Net.Ru

We consider finite-codimensional Chebyshev subspaces in the complex space $C(Q)$, where $Q$ is a compact Hausdorff space, and prove analogs of some theorems established earlier for the real case by Garkavi and Brown (in particular, we characterize such subspaces). It is shown that if the real space $C(Q)$ contains finite-codimensional Chebyshev subspaces, then the same is true of the complex space $C(Q)$ (with the same $Q$).

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