Kominek, Zygfryd Remarks on the stability of some quadratic functional equations. (English) Zbl 1168.39011 Opusc. Math. 28, No. 4, 517-527 (2008). Reviewer: Jacek Chmieliński (Kraków) MSC: 39B82 39B22 39B52 PDF BibTeX XML Cite \textit{Z. Kominek}, Opusc. Math. 28, No. 4, 517--527 (2008; Zbl 1168.39011)
Kominek, Zygfryd Boundedness and linearity of additive functionals. (English) Zbl 0832.46004 Opusc. Math. 14, 83-87 (1994). MSC: 46A99 28A10 46A20 46A22 PDF BibTeX XML Cite \textit{Z. Kominek}, Opusc. Math. 14, 83--87 (1994; Zbl 0832.46004)