@article{BSMF_1923__51__244_1,
     author = {Kogbetliantz, E.},
     title = {Sur la sommabilit\'e de la s\'erie ultrasph\'erique \`a l{\textquoteright}int\'erieur de l{\textquoteright}intervalle $(- 1, + 1)$ par la m\'ethode des moyennes arithm\'etiques},
     journal = {Bulletin de la Soci\'et\'e Math\'ematique de France},
     pages = {244--295},
     publisher = {Soci\'et\'e math\'ematique de France},
     volume = {51},
     year = {1923},
     doi = {10.24033/bsmf.1040},
     language = {fr},
     url = {http://www.numdam.org/articles/10.24033/bsmf.1040/}
}