@article{GDZPPN002136252,
title = {Trigonometric Convolution Operators with Kernels having Alternating Signs and their Degree of Convergence.},
journal = {Jahresbericht der Deutschen Mathematiker-Vereinigung},
volume = {70},
year = {1967},
pages = {86-99},
zbl = {0177.31201},
url = {http://dml.mathdoc.fr/item/GDZPPN002136252}
}
Butzer, P.L.; Scherer, K.; Nessel, R.J. Trigonometric Convolution Operators with Kernels having Alternating Signs and their Degree of Convergence.. Jahresbericht der Deutschen Mathematiker-Vereinigung, Tome 70 (1967) pp. 86-99. http://gdmltest.u-ga.fr/item/GDZPPN002136252/