1. A characterization of sets and operations invariant under bijections

   • Lech Bartłomiejczyk
   • Józef Drewniak

   Research paper 01 August 2004 Pages: 1 - 9

2. On a symmetric functional equation in two variables

   • Nicole Brillouët-Belluot

   Research paper 01 August 2004 Pages: 10 - 20

3. Analytic solutions of an iterative functional equation

   • Wen Rong Li
   • Sui Sun Cheng

   Research paper 01 August 2004 Pages: 21 - 27

4. On the measurability and the Baire property of t-Wright-convex functions

   • Andrzej Olbryś

   Research paper 01 August 2004 Pages: 28 - 37

5. A characterization of constant width in Minkowski planes

   • Gennadiy Averkov
   • Horst Martini

   Research paper 01 August 2004 Pages: 38 - 45

6. On when the multiplicative center of a near-ring is a subnear-ring

   • Erhard Aichinger
   • Mark Farag

   Research paper 01 August 2004 Pages: 46 - 59

7. On covariant embeddings of a linear functional equation with respect to an analytic iteration group in some non-generic cases

   • Harald Fripertinger
   • Ludwig Reich

   Research paper 01 August 2004 Pages: 60 - 87

8. Une remarque sur les «logarithmes» associés à certains caractères

   • Anne Duval

   Research paper 01 August 2004 Pages: 88 - 97

9. Subdirectly irreducible algebras with various equations

   • Vahan Toghanyan

   Research paper 01 August 2004 Pages: 98 - 107

10. Remarks on the stability of Drygas’ equation and the Pexider-quadratic equation

    • Dilian Yang

    Research paper 01 August 2004 Pages: 108 - 116

11. The functional equation \( f(x)f(y)f(z) = f(x) + f(y) + f(z) \)

    • Walter Benz

    Short communication 01 August 2004 Pages: 117 - 120