@incollection{MSMF_1972__31-32__133_0,
     author = {De Giorgi, Ennio},
     title = {Sur l'existence de solutions analytiques d'\'equations \`a coefficients constants},
     booktitle = {Colloque d'analyse fonctionnelle (Bordeaux, 1971)},
     author = {Collectif},
     series = {M\'emoires de la Soci\'et\'e Math\'ematique de France},
     pages = {133--135},
     publisher = {Soci\'et\'e math\'ematique de France},
     number = {31-32},
     year = {1972},
     doi = {10.24033/msmf.74},
     zbl = {0243.35008},
     mrnumber = {50 #7779},
     url = {http://archive.numdam.org/articles/10.24033/msmf.74/}
}

De Giorgi, Ennio. Sur l'existence de solutions analytiques d'équations à coefficients constants, dans Colloque d'analyse fonctionnelle (Bordeaux, 1971), Mémoires de la Société Mathématique de France, no. 31-32 (1972), pp. 133-135. doi : 10.24033/msmf.74. http://archive.numdam.org/articles/10.24033/msmf.74/