@article{02142130,
title = {Quasiderivatives and interior smoothness of harmonic functions associated with degenerate diffusion processes.},
journal = {Electronic Communications in Probability [electronic only]},
volume = {9},
year = {2004},
pages = {615-633},
zbl = {1064.60172},
language = {en},
url = {http://dml.mathdoc.fr/item/02142130}
}
Krylov, N.V. Quasiderivatives and interior smoothness of harmonic functions associated with degenerate diffusion processes.. Electronic Communications in Probability [electronic only], Tome 9 (2004) pp. 615-633. http://gdmltest.u-ga.fr/item/02142130/