An eigenfunction expansion method for problems with overspecified data
Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Serie 3, Volume 19 (1965) no. 3, p. 397-405 
@article{ASNSP_1965_3_19_3_397_0,
     author = {Miller, Keith},
     title = {An eigenfunction expansion method for problems with overspecified data},
     journal = {Annali della Scuola Normale Superiore di Pisa - Classe di Scienze},
     publisher = {Scuola normale superiore},
     volume = {Ser. 3, 19},
     number = {3},
     year = {1965},
     pages = {397-405},
     zbl = {0145.14301},
     mrnumber = {183972},
     language = {en},
     url = {http://www.numdam.org/item/ASNSP_1965_3_19_3_397_0}
}

Miller, Keith. An eigenfunction expansion method for problems with overspecified data. Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Serie 3, Volume 19 (1965) no. 3, pp. 397-405. http://www.numdam.org/item/ASNSP_1965_3_19_3_397_0/

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