no. 1
Euler-Poincaré index theory on Banach manifolds
Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 4, Tome 2 (1975) no. 1, pp. 89-106. 
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     author = {Tromba, A. J.},
     title = {Euler-Poincar\'e index theory on {Banach} manifolds},
     journal = {Annali della Scuola Normale Superiore di Pisa - Classe di Scienze},
     pages = {89--106},
     publisher = {Scuola normale superiore},
     volume = {Ser. 4, 2},
     number = {1},
     year = {1975},
     mrnumber = {385913},
     zbl = {0315.58006},
     language = {en},
     url = {http://archive.numdam.org/item/ASNSP_1975_4_2_1_89_0/}
}
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Tromba, A. J. Euler-Poincaré index theory on Banach manifolds. Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 4, Tome 2 (1975) no. 1, pp. 89-106. http://archive.numdam.org/item/ASNSP_1975_4_2_1_89_0/

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