no. 3
Analytic regularity for the Dirichlet problem in domains with conic singularities
Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 4, Tome 4 (1977) no. 3, pp. 515-530. 
@article{ASNSP_1977_4_4_3_515_0,
     author = {Baouendi, Mohamed Salah and Sj\"ostrand, Johannes},
     title = {Analytic regularity for the Dirichlet problem in domains with conic singularities},
     journal = {Annali della Scuola Normale Superiore di Pisa - Classe di Scienze},
     pages = {515--530},
     publisher = {Scuola normale superiore},
     volume = {Ser. 4, 4},
     number = {3},
     year = {1977},
     zbl = {0372.35012},
     mrnumber = {509597},
     language = {en},
     url = {archive.numdam.org/item/ASNSP_1977_4_4_3_515_0/}
}
Baouendi, M. S.; Sjöstrand, J. Analytic regularity for the Dirichlet problem in domains with conic singularities. Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 4, Tome 4 (1977) no. 3, pp. 515-530. http://archive.numdam.org/item/ASNSP_1977_4_4_3_515_0/

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