no. 1
A KAM-theorem for some nonlinear partial differential equations
Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 4, Tome 23 (1996) no. 1, pp. 119-148. 
@article{ASNSP_1996_4_23_1_119_0,
     author = {P\"oschel, J\"urgen},
     title = {A KAM-theorem for some nonlinear partial differential equations},
     journal = {Annali della Scuola Normale Superiore di Pisa - Classe di Scienze},
     pages = {119--148},
     publisher = {Scuola normale superiore},
     volume = {Ser. 4, 23},
     number = {1},
     year = {1996},
     zbl = {0870.34060},
     mrnumber = {1401420},
     language = {en},
     url = {archive.numdam.org/item/ASNSP_1996_4_23_1_119_0/}
}
Pöschel, Jürgen. A KAM-theorem for some nonlinear partial differential equations. Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 4, Tome 23 (1996) no. 1, pp. 119-148. http://archive.numdam.org/item/ASNSP_1996_4_23_1_119_0/

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