@article{ASNSP_1968_3_22_2_343_0, author = {Bruckner, A. M. and Rosenfeld, Melvin}, title = {A theorem on approximate directional derivatives}, journal = {Annali della Scuola Normale Superiore di Pisa - Classe di Scienze}, pages = {343--350}, publisher = {Scuola normale superiore}, volume = {Ser. 3, 22}, number = {2}, year = {1968}, zbl = {0155.10503}, mrnumber = {247012}, language = {en}, url = {archive.numdam.org/item/ASNSP_1968_3_22_2_343_0/} }
Bruckner, A. M.; Rosenfeld, M. A theorem on approximate directional derivatives. Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 3, Tome 22 (1968) no. 2, pp. 343-350. http://archive.numdam.org/item/ASNSP_1968_3_22_2_343_0/
[1] Theory of the Integral, Monografie Matematyczne7, Warszawa - Lwow, 1937. | JFM 63.0183.05
,[2] Sur les conditions de l'existence de la differentielle tolale, Rec. Math. Soc. Math. Moscow (Mat Sb.) 32 (1925) 511-526. | JFM 51.0207.07
,[3] On totally differentiable and smooth functions, Pac. J. Math. 1 (1951) 143-159. | MR 43878 | Zbl 0043.05803
,