1. C. Alsina, J.L. Garcia-Roig, On continuous preservation of norms and areas, Aequationes Math. 38 (1989), 211-215.
2. C. Alsina, J.L. Garcia-Roig, On the functional equation |T(x)◦T(y)| = |x◦y|, Constantin Carathéodory: An International Tribute, ed. by Th.M. Rassias, World Scientific Publ. Co. 1991, 47-52.
3. J. Chmieliński, On the Hyers-Ulam stability of the generalized orthogonality equation in real Hilbert spaces, to appear.
4. J. Chmieliński, On the stability of the generalized orthogonality equation, to appear.
5. R. Ger, Superstability is not natural, Rocznik Naukowo - Dydaktyczny WSP w Krakowie, Prace Matematyczne XIII (Annales de l'Ecole Normale Supérieure à Cracovie, Travaux Mathématiques XIII), Kraków 1993, 109-123.
6. D.H. Hyers, On the stability of the linear functional equation, Proc. Nat. Acad. Sci. U.S.A. 27 (1941), 222-224.
7. J.S. Lomont, P. Mendelson, The Wigner unitarity-antiunitarity theorem, Ann. of Math. 78 (1963), 548-559.
8. J. Rätz, Remarks on Wigner's Theorem, talk given during 31-st International Symposium on Functional Equations, Debrecen, Hungary 1993.
9. E.P. Wigner, Gruppentheorie und ihre Anwendungen auf die Quantenmechanik der Atomspektren, Friedr. Vieweg und Sohn Akt.-Ges., 1931, 251.
Google Scholar
10.1515/amsil
English