Globally regular solutions to the u 5 Klein-Gordon equation
Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Serie 4, Volume 15 (1988) no. 3, p. 495-513 
@article{ASNSP_1988_4_15_3_495_0,
     author = {Struwe, Micha\"el},
     title = {Globally regular solutions to the $u^5$ Klein-Gordon equation},
     journal = {Annali della Scuola Normale Superiore di Pisa - Classe di Scienze},
     publisher = {Scuola normale superiore},
     volume = {Ser. 4, 15},
     number = {3},
     year = {1988},
     pages = {495-513},
     zbl = {0728.35072},
     mrnumber = {1015805},
     language = {en},
     url = {http://www.numdam.org/item/ASNSP_1988_4_15_3_495_0}
}

Struwe, Michael. Globally regular solutions to the $u^5$ Klein-Gordon equation. Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Serie 4, Volume 15 (1988) no. 3, pp. 495-513. http://www.numdam.org/item/ASNSP_1988_4_15_3_495_0/

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