@article{BSMF_1962__90__449_0, author = {Kotake, Takeshi and Narasimhan, Mudumbai S.}, title = {Regularity theorems for fractional powers of a linear elliptic operator}, journal = {Bulletin de la Soci\'et\'e Math\'ematique de France}, pages = {449--471}, publisher = {Soci\'et\'e math\'ematique de France}, volume = {90}, year = {1962}, doi = {10.24033/bsmf.1584}, mrnumber = {26 #6819}, zbl = {0104.32503}, language = {en}, url = {http://archive.numdam.org/articles/10.24033/bsmf.1584/} }