Studies on extremal problems of spline-approximation

@article{Velikin1990StudiesOE,
title={Studies on extremal problems of spline-approximation},
author={V. L. Velikin and N. A. Nazarenko},
journal={Ukrainian Mathematical Journal},
year={1990},
volume={42},
pages={28-50}
}

We give a survey of the most important results on extremal problems of approximation by splines which were obtained by N. P. Korneichuk or stimulated by the methods he developed.