On functions of rectangles and their application to analytic functions
Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 2, Tome 3 (1934) no. 1, p. 27-32 
@article{ASNSP_1934_2_3_1_27_0,
     author = {Saks, Stanislaw and Zygmund, Antoni},
     title = {On functions of rectangles and their application to analytic functions},
     journal = {Annali della Scuola Normale Superiore di Pisa - Classe di Scienze},
     publisher = {Scuola normale superiore},
     volume = {Ser. 2, 3},
     number = {1},
     year = {1934},
     pages = {27-32},
     language = {en},
     url = {http://www.numdam.org/item/ASNSP_1934_2_3_1_27_0}
}

Saks, Stanislaw; Zygmund, Antoni. On functions of rectangles and their application to analytic functions. Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 2, Tome 3 (1934) no. 1, pp. 27-32. http://www.numdam.org/item/ASNSP_1934_2_3_1_27_0/

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