On an extension of a theorem of O. Szàsz
Compositio Mathematica, Tome 17 (1965-1966) , pp. 281-285. 
@article{CM_1965-1966__17__281_0,
     author = {Hsiang, Fu Cheng},
     title = {On an extension of a theorem of O. Sz\`asz},
     journal = {Compositio Mathematica},
     pages = {281--285},
     publisher = {Kraus Reprint},
     volume = {17},
     year = {1965-1966},
     zbl = {0163.07803},
     mrnumber = {204975},
     language = {en},
     url = {archive.numdam.org/item/CM_1965-1966__17__281_0/}
}
Hsiang, Fu Cheng. On an extension of a theorem of O. Szàsz. Compositio Mathematica, Tome 17 (1965-1966) , pp. 281-285. http://archive.numdam.org/item/CM_1965-1966__17__281_0/

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