On spectral projections of elliptic operators
Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 3, Tome 24 (1970) no. 2, p. 209-230 
@article{ASNSP_1970_3_24_2_209_0,
     author = {Burak, Tamar},
     title = {On spectral projections of elliptic operators},
     journal = {Annali della Scuola Normale Superiore di Pisa - Classe di Scienze},
     publisher = {Scuola normale superiore},
     volume = {Ser. 3, 24},
     number = {2},
     year = {1970},
     pages = {209-230},
     zbl = {0207.41301},
     mrnumber = {279633},
     language = {en},
     url = {http://www.numdam.org/item/ASNSP_1970_3_24_2_209_0}
}

Burak, T. On spectral projections of elliptic operators. Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 3, Tome 24 (1970) no. 2, pp. 209-230. http://www.numdam.org/item/ASNSP_1970_3_24_2_209_0/

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