@article{1183527955,
author = {Butzer, P. L. and Nessel, R. J.},
title = {Favard classes for $n$-dimensional singular integrals},
journal = {Bull. Amer. Math. Soc.},
volume = {72},
number = {4},
year = {1966},
pages = { 493-498},
language = {en},
url = {http://dml.mathdoc.fr/item/1183527955}
}
Butzer, P. L.; Nessel, R. J. Favard classes for $n$-dimensional singular integrals. Bull. Amer. Math. Soc., Tome 72 (1966) no. 4, pp. 493-498. http://gdmltest.u-ga.fr/item/1183527955/