@article{1250128926,
author = {Kohn, M.K.},
title = {Symmetric derivatives defined by weighted spherical means},
journal = {Rocky Mountain J. Math.},
volume = {10},
number = {4},
year = {1980},
pages = { 351-370},
language = {en},
url = {http://dml.mathdoc.fr/item/1250128926}
}
Kohn, M.K. Symmetric derivatives defined by weighted spherical means. Rocky Mountain J. Math., Tome 10 (1980) no. 4, pp. 351-370. http://gdmltest.u-ga.fr/item/1250128926/