@article{GDZPPN002314711,
title = {Trigonometrie Approximation with Exponential Error Orders. I. Construction of Asymptotically Optimal Processes; Generalized de la Vall\'ee Poussin Sums.},
journal = {Mathematische Annalen},
volume = {229},
year = {1977},
pages = {57-74},
zbl = {0342.42002},
url = {http://dml.mathdoc.fr/item/GDZPPN002314711}
}
Dahmen, Wolfgang. Trigonometrie Approximation with Exponential Error Orders. I. Construction of Asymptotically Optimal Processes; Generalized de la Vallée Poussin Sums.. Mathematische Annalen, Tome 229 (1977) pp. 57-74. http://gdmltest.u-ga.fr/item/GDZPPN002314711/