1. Bisymmetric and quasitrivial operations: characterizations and enumerations

   • Jimmy Devillet

   OriginalPaper 24 April 2019 Pages: 501 - 526

2. An extension of the Hermite–Hadamard inequality for convex and s-convex functions

   • Péter Kórus

   OriginalPaper Open access 22 March 2019 Pages: 527 - 534

3. Functional equations for exponential polynomials

   • Żywilla Fechner
   • László Székelyhidi

   OriginalPaper Open access 11 August 2018 Pages: 535 - 545

4. A new orthogonality and angle in a normed space

   • M. Nur
   • H. Gunawan

   OriginalPaper 14 July 2018 Pages: 547 - 555

5. On a functional equation characterizing linear similarities

   • Paweł Wójcik

   OriginalPaper Open access 17 October 2018 Pages: 557 - 561

6. Sur certaines équations fonctionnelles approchées, liées à la transformation de Gauss

   • Michel Balazard
   • Bruno Martin

   OriginalPaper 16 August 2018 Pages: 563 - 585

7. Necessary and sufficient conditions for nonlinear matrix identities to always hold

   • Bo Jiang
   • Yongge Tian

   OriginalPaper 09 November 2018 Pages: 587 - 600

8. Compositions with a fixed number of inversions

   • A. Knopfmacher
   • M. E. Mays
   • S. Wagner

   OriginalPaper 10 May 2018 Pages: 601 - 617

9. An inequality for the length of isoptic chords of convex bodies

   • Jesús Jerónimo-Castro
   • Carlos Yee-Romero

   OriginalPaper 09 November 2018 Pages: 619 - 628

10. Derivations and Leibniz differences on rings

    • Bruce Ebanks

    OriginalPaper 08 September 2018 Pages: 629 - 640

11. The images of orthogonally additive mappings from inner product spaces to groups

    • Imke Toborg

    OriginalPaper 18 July 2018 Pages: 641 - 650