On the functional equation f(x+y) =f(x) +f(y)

Instytut Matematyczny Polskiej Akademii Nauk / Institute of Mathematics / Publishing house / Journals and Serials / Fundamenta Mathematicae / All issues

H. Kestelman Fundamenta Mathematicae 34 (1947), 144-147 DOI: 10.4064/fm-34-1-144-147