Abschätzung nach unten für Lösungen nichtlinearer Differentialungleichungen
Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Serie 3, Volume 27 (1973) no. 3, p. 441-456 
@article{ASNSP_1973_3_27_3_441_0,
     author = {Redheffer, Ray},
     title = {Absch\"atzung nach unten f\"ur L\"osungen nichtlinearer Differentialungleichungen},
     journal = {Annali della Scuola Normale Superiore di Pisa - Classe di Scienze},
     publisher = {Scuola normale superiore},
     volume = {Ser. 3, 27},
     number = {3},
     year = {1973},
     pages = {441-456},
     zbl = {0302.35024},
     language = {de},
     url = {http://www.numdam.org/item/ASNSP_1973_3_27_3_441_0}
}

Redheffer, Ray. Abschätzung nach unten für Lösungen nichtlinearer Differentialungleichungen. Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Serie 3, Volume 27 (1973) no. 3, pp. 441-456. http://www.numdam.org/item/ASNSP_1973_3_27_3_441_0/

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