List of publications by László Székelyhidi

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  1. L. Székelyhidi, Characterization of Locally Compact Abelian Groups Having Spectral Synthesis, submitted
  2. L. Székelyhidi, Spectral Synthesis on Direct Products, arXiv:2308.10867 [math.FA]
  3. L. Székelyhidi, New Results on Spectral Synthesis, arXiv:2307.16016 [math.FA]
  4. L. Székelyhidi, Spectral synthesis on varieties, submitted, arXiv: 2306.17438 [math.FA]
  5. L. Székelyhidi, A generalization of the Heisenberg group, Jour. Iranian Math. Soc. (JIMS), 4(2), 105-119, 2023. 
  6. Z. Fechner, E. Gselmann, and L. Székelyhidi, Endomorphisms and derivations of the measure algebra of commutative hypergroups, to appear in Indag. Math.
  7.  Z. Fechner, E. Gselmann, and L. Székelyhidi, Generalized derivations and generalized exponential monomials on hypergroups, Opuscula Math. 43(4):493-505, 2023.
  8. L. Székelyhidi, Finite dimensional varieties over the Heisenberg group, Aequationes Math., 97(2):377–390, 2023.
  9. Z. Fechner, E. Gselmann, and L. Székelyhidi, Spectral synthesis via moment functions on hypergroups, Forum Math., 34(5):1187–1197, 2022.
  10. Z. Fechner, E. Gselmann, and L. Székelyhidi, Moment functions of higher rank on polynomial hypergroups, Adv. Oper. Theory, 7,41, 2022.
  11. Z. Fechner, E. Gselmann, and L. Székelyhidi, Moment functions and exponential monomials on commutative hypergroups, Aequationes Math., 95:1281–1290, 2021.
  12. E. Gselmann and L. Székelyhidi, Symmetric spectral synthesis, Aequationes Math., 95(2):255–279, 2021.
  13. Z. Fechner and L. Székelyhidi, Finite dimensional varieties on hypergroups, Aequationes Math., 95(3):551–567, 2021.
  14. L. Székelyhidi, S. M. Tabatabaie, and K. Vati, Strictly and strongly positive definite functions on locally compact hypergroups, Results Math., 76(3):156, 12, 2021.
  15. Fechner, E. Gselmann and L. Székelyhidi, Moment functions on groups., Results Math., 76(4):171, 16, 2021.
  16. L. Székelyhidi, Spectral analysis and synthesis on an infinite hypergroup join, Publ. Math. Debrecen, 99(3-4):261–273, 2021.
  17. Z. Fechner and L. Székelyhidi, Moment functions on double coset hypergroups, to appear in Results in Math.
  18. L. Székelyhidi, Spherical spectral synthesis on hypergroups,   Acta Math. Hungar., 163(1):247–275, 2021.
  19. Z. Fechner and L. Székelyhidi, Finite dimensional varieties on hypergroups, Aequationes Math., 2021
  20. E. Gselmann and L. Székelyhidi, Symmetric spectral synthesis, Aequationes Math., 2021
  21. L. Székelyhidi, Note on the semi-simplicity of measure algebras,   Monatsh. Math., 192:935–938, 2020.
  22. Z. Fechner and L. Székelyhidi, Remarks on infinite hypergroup joins,  Ann. Univ. Sci. Budapest. Sect. Comput., 51:89–95, 2020.
  23. L. Székelyhidi, Laudation to Professor Antal Járai on his seventieth birthday,   Ann. Univ. Sci. Budapest. Sect. Comput., 51:19–26, 2020.
  24. L. Székelyhidi, Invariant means in stability theory, In  Ulam Type Stability, Springer International Publishing, Springer, Cham, 409–451, 2019.
  25. L. Székelyhidi, Spectral synthesis and partial differential equations,   Acta Math. Hungar., 161(1):31–47, 2020.
  26. L. Székelyhidi,  Spectral synthesis on the affine group of SU(n),   Acta Math. Hungar., 158:352–362, 2019.
  27. L. Székelyhidi and K. Vati, Exponential monomials on hypergroup joins,    Miskolc Math. Notes, 21(1):463–472, 2020.
  28. Fechner and L. Székelyhidi, Spherical and moment functions on the affine group of SU(n), Acta Math. Hungar., 157(1):10-26, 2019.
  29. Fechner and L. Székelyhidi, Moment Functions on Affine Groups, Results Math., vol. 74(1), Art. 5, 13 pp., 2019.
  30. Z. Fechner and L. Székelyhidi, Functional equations for exponential polynomials, Aequationes Math., Aequationes Math., 93(3):535-545, 2019.
  31. L. Székelyhidi and K. Vati, Moment functions on hypergroup joins, Adv. Pure Appl. Math., 10(3):215-220, 2019.
  32. L. Székelyhidi, Functional Equations on Affine Groups, Chapter 3, In Advanced topics in mathematical analysis, pages 71-94. CRC Press, Boca Raton, FL, 2019.
  33. L. Székelyhidi, S. M. Tabatabaie and B. Sadathosseyni, Convolution operators on measure algebras of KPC–hypergroups, Adv. Pure Appl. Math., vol. 10(1), pp. 1-6, 2019.
  34. L. Szekelyhidi and S. M. Tabatabaie, Invariant subspaces on KPC-hypergroups Zh. Mat. Fiz. Anal. Geom., 15(1):122-130, 2019.
  35. L. Székelyhidi, Spectral Synthesis and its Applications, Chapter 7 in Mathematical Analysis and Applications, Wiley, pp. 193-254, 2018.
  36. L. Székelyhidi, Superstability of functional equations related to spherical functions,  Open Math., 15:427-432, 2017.
  37. L. Székelyhidi and B. Wilkens, Spectral synthesis and residually finite dimensional algebra,  Jou. Algebra and its Appl., 16(10):1-10, 2017.
  38. L. Székelyhidi, Functional equations and stability problems on hypergroups, Chapter 14, Developments in Functional Equations and Related Topics, Springer Optimization and Its Applications 124, 2017
  39. Székelyhidi, Spherical monomials on affine groups, Ann. Univ. Sci. Budapest. Sect. Comput., 48:209-223, 2018.
  40. L. Székelyhidi, Continuation of the Laudation to Professor Zoltán Daróczy on his eightieth birthday, Ann. Univ. Sci. Budapest., Sect. Comp., vol.47, pp.9-18, 2018.
  41. L. Székelyhidi, Spherical monomials on affine groups, Ann. Univ. Sci. Budapest, Sect. Comp., vol. 48, 209-223, 2018.
  42. Székelyhidi, Spectral synthesis and Euclidean motions, Math. Pannon., 26(1):33-46, 2017/18.
  43. Székelyhidi, Functional Equations and Stability Problems on Hypergroups, in Developments in Functional Equations and Related Topics, Springer International Publishing, pp. 305-331, 2017.
  44. L. Székelyhidi and B. Wilkens, Spectral synthesis and residually finite dimensional algebras,  Jour. of Algebra and Its Appl., vol. 16(10), pp. 1-10, 2017.
  45. L. Székelyhidi, Superstability of functional equations related to spherical functions, Open Math., vol. 15, pp. 427-432, 2017
  46. L. Szekelyhidi, On spectral synthesis in several variables,  Adv. Operator Theory, vol. 2, pp. 179-191, 2017 
  47. L. Szekelyhidi and K. Vati, Functional equations on hypergroup joins, Arch. Math. (Basel), vol. 109, no. 1, pp. 41-47, 2017
  48. L. Szekelyhidi, Invariant means on double coset spaces, Periodica Math., vol. 75, no. 1, pp. 58-65, 2017
  49. Z. Fechner and L. Székelyhidi, Functional equations on double coset hypergroups, Funct. Anal., vol. 8, pp. 411-423, 2017
  50. Z. Fechner and L. Székelyhidi, Sine and cosine equations on hypergroups, Banach J. Math. Anal., 2017, vol. 11(4), pp. 808-824, 2017.
  51. L. Szekelyhidi, Spherical spectral synthesis, Acta Math. Hung., pp. 111-117, 2016 
  52. L. Szekelyhidi and L.Vajday, Spectral Synthesis on Commutative Hypergroups, Annales Univ. Sci. Budapest., Sect. Comp., vol. 45, pp. 111-117, 2016
  53. L. Szekelyhidi, On the principal ideal theorem and spectral synthesis on discrete Abelian groups, Acta Math. Hungar., vol. 150, no. 1, pp. 228-233, 2016
  54. Z. Fechner and L. Székelyhidi, Sine functions on hypergroups, Archiv. der Math., vol. 106, no. 4, pp. 371-382, 2016.
  55. L. Székelyhidi, On the powers of maximal ideals in the measure algebra, Banach J. Math. Anal., vol. 10, no. 2, pp. 385-399, 2016.
  56. J. M. Almira and L. Székelyhidi, Montel-type theorems for exponential polynomials, Demonstratio Math., vol. 49, no. 2, pp. 197-212, 2016.
  57. L. Székelyhidi, Remark on the graph of additive functions, Aequationes Math., vol. 90, no. 1., pp. 7-9, 2016.
  58. J. M. Almira and L. Székelyhidi, Characterization of Classes of Polynomial Functions, Med. J. Math., vol. 13, no 1, pp. 301-307, 2016.
  59. J. M. Almira and L. Székelyhidi, On the closure of translation-dilation invariant linear spaces of polynomials, Results in Math., vol. 69, pp. 263-272, 2016.
  60. Z. Fechner and L. Székelyhidi, A generalization of Gajda’s equation on commutative topological groups, Publ. Math. Debrecen, vol. 88, no. 1-2, pp. 163-176, 2016.
  61. L. Székelyhidi and B. Wilkens, Spectral analysis and synthesis on varieties, Jour. Math. Anal. App., vol. 433, pp. 1329-1332, 2016.
  62. L. Székelyhidi, Annihilator methods for spectral synthesis on locally compact Abelian groups, Monatsh. für Math., vol. 69, pp. 263-272, 2016.
  63. L. Székelyhidi, Spectral synthesis on special varieties, Annales Univ. Sci. Sectio. Comp., vol. 44, pp. 29-36, 2015.
  64. L. Székelyhidi, Stability of Functional Equations on Hypergroups, Aequationes Math., vol. 89, no. 6., pp. 1475-1483, 2015.
  65. L. Székelyhidi, A Functional Equation for Exponential Polynomials, Aequationes Math., vol. 89, no. 3, pp. 821-828, 2015.
  66. M. Almira and L. Székelyhidi, Local polynomials and the Montel theorem, Aequationes Math., vol. 89, no. 2, pp. 329-338, 2015.
  67. L. Székelyhidi, Annihilator methods in discrete spectral synthesis, Acta Math. Hung., vol. 143, no. 2, pp. 351-366, 2014.
  68. L. Székelyhidi, On Fréchet’s functional equation, Monatsh. für Math., vol. 175, no. 4, pp. 639-643, 2014.
  69. G. Horváth, L. Székelyhidi and B. Wilkens, Non-synthesizable varieties, Jour. Math. Anal. App., vol. 417, pp. 394–399, 2014.
  70. L. Székelyhidi, Characterization of exponential polynomials on hypergroups, Ann. Funct. Anal., vol. 5, no. 2, pp. 53–60, 2014.
  71. L.Székelyhidi, A characterization of exponential polynomials, Publ. Math. Debrecen, vol. 83, no. 4, pp. 757–771, 2013.
  72. Zs. Páles and L. Székelyhidi, Laudation to Zoltán Daróczy, Annales Univ. Sci. Budapest, Sect. Comp., vol. 40, pp. 9–20, 2013.
  73. L. Székelyhidi and L. Vajday, On Conditional Functional Equations with Applications on Hypergroups, Annales Univ. Sci. Budapest., Sect. Comp., vol. 41, pp. 323–332, 2013.
  74. L. Székelyhidi, Exponential polynomials on commutative hypergroups, Arch. Math., vol. 101, no. 4, pp. 341–347, 2013.
  75. L. Székelyhidi, The Levi-Civitá Equation, Vector Modules and Spectral Synthesis, Recent Developments in Functional Equations and Inequalities, Banach Center Publications, vol. 99, pp. 193–206, 2013.
  76. L. Székelyhidi, Spectral Synthesis Problems on Hypergroups, Annales Univ. Sci. Budapest., Sect. Comp., vol. 39, pp. 439–447, 2013.
  77. L. Székelyhidi, Spectral Analysis and Spectral Synthesis, in Nonlinear Analysis: Stability, Approximation, and Inequalities In Honor of Themistocles M. Rassias’ 60th Birthday (Panos Pardalos, Hari M. Srivastava, and P. Georgiev eds.), vol. 68, pp. 707–719, 2012.
  78. L. Székelyhidi and L. Vajday, Functional equations on the SU(2)-hypergroup, Math. Pannonica, vol. 23, no. 2, pp. 187–193, 2012.
  79. L. Székelyhidi and L. Vajday, Spectral Analysis and Moment Functions, Jour. Inf. Math. Sci., vol. 4, no. 2, pp. 185–188, 2012.
  80. L. Székelyhidi and L. Vajday, A moment problem on some types of hypergroups, Ann. Funct. Anal., vol. 3, no. 2, pp. 58–65, 2012.
  81. L. Székelyhidi, Polynomial Functions and Spectral Synthesis on Abelian Groups, Banach J. Math. Anal., vol. 6, no. 1, pp. 124–131, 2012.
  82. L. Székelyhidi, Noetherian Rings of Polynomial Functions on Abelian Groups, Aequationes Math., vol. 84, no. 1, pp. 41–50, 2012.
  83. L. Székelyhidi, Fourier transform for mean periodic functions, Annales Univ. Sci. Budapest, vol. 35, pp. 267–284, 2011.
  84. L. Székelyhidi and L. Vajday, Spectral analysis on commutative hyper-groups, Aequationes Math., vol. 80(1-2), pp. 223–226, 2010.
  85. L. Székelyhidi, Spectral synthesis problems on locally compact groups, Monats. Math., vol. 161(2), pp. 223–232, 2010.
  86. A. Orosz and L. Székelyhidi, Moment functions on Sturm–Liouville– hypergroups, Annales Univ. Sci Budapest, Sect. Comp., vol. 29, pp. 141– 156, 2008.
  87. L. Székelyhidi, D’Alembert’s Functional Equation on Compact Groups, Banach J. Math. Anal., vol. 1, No. 2, pp. 221–226, 2007.
  88. L. Székelyhidi, Superstability of moment functions on hypergroups, Nonlinear Funct. Anal. Appl., vol. 11, pp. 815–821, 2006.
  89. L. Székelyhidi, Spectral Synthesis on Multivariate Polynomial Hyper-groups, Monats. Math., vol. 153, pp. 145–152, 2008.
  90. M. Laczkovich and L. Székelyhidi, Spectral synthesis on discrete abelian groups, Math. Proc. Camb. Phil. Soc., vol. 143(01), pp. 103–120, 2007.
  91. L. Székelyhidi, Functional Equations on Sturm–Liouville Hypergroups, Math. Pannonica, vol. 17(2), pp. 169–182, 2006.
  92. S. Moslehian and L. Székelyhidi, Stability of ternary homomorphisms via generalized Jensen equation, Results in Math., vol. 49(3-4), pp. 289– 300, 2006.
  93. L. Székelyhidi, Discrete spectral synthesis, Ann. Math. Inform., vol. 32, pp. 141–152, 2005.
  94. M. S. Moslehian and L. Székelyhidi, Stability of ternary homomorphisms via generalized Jensen equation, http://arxiv.org/math., FA/0511540. (electronic) 2005.
  95. L. Székelyhidi, Polynomial functions and spectral synthesis, Aequationes Math., vol. 70(1–2), pp. 122–130, 2005.
  96. A. Orosz and L. Székelyhidi, Moment Functions on Polynomial Hyper-groups, Arch. Math., vol. 85, pp. 141–150, 2005.
  97. B. Ebanks and L. Székelyhidi, On multiplicative and additive differences, Aequationes Math., vol. 69, pp. 97–113, 2005.
  98. A. Bereczky, and L. Székelyhidi, Spectral synthesis on torsion groups, Jour. Math. Anal. Appl. vol. 304(2), pp. 607–613, 2005.
  99. L. Székelyhidi, Spectral synthesis and a characterization of polynomial ideals, Publ. Math. Debrecen vol. 66(1–2), pp. 183–195, 2005.
  100. L. Székelyhidi, Difference equations via spectral synthesis, Annales Univ. Sci. Budapest, Sect. Comp., vol. 24, pp. 3–14, 2004.
  101. A. Orosz and L. Székelyhidi, Moment Functions on Polynomial Hyper-groups in Several Variables, Publ. Math. Debrecen vol. 65(3–4), pp. 429– 438, 2004.
  102. Z. Páles and L. Székelyhidi, On approximate sandwich and decomposition theorems, Annales Univ. Sci. Budapest, Sect. Comp. vol. 23, pp. 59– 70, 2004.
  103. L. Székelyhidi, Spectral Analysis and Spectral Synthesis on Polynomial Hypergroups, Monatshefte Math. vol. 141(1), pp. 33–43, 2004.
  104. L. Székelyhidi, The failure of spectral synthesis on some types of discrete Abelian groups, Jour. Math. Anal. Appl. vol. 291, pp. 757–763, 2004.
  105. P. K. Sahoo and L. Székelyhidi, On the general solution of a functional equation on ZxZ, Arch. Math., vol. 81, pp. 233–239, 2003.
  106. J. K. Chung, P. Sahoo and L. Székelyhidi, On quadratic differences that depend on the product of arguments – revisited, Aequationes Math., vol. 67, pp. 216–224, 2004.
  107. L. Székelyhidi, Functional Equations on Hypergroups, in Functional Equations, Inequalities and Applications (Th. M. Rassias, ed.), pp. 167– 181, Kluwer Academic Publishers, 2003.
  108. L. Székelyhidi, On a Paper of T. M. K. Davison, Annales Acad. Paedag. Cracov., Studia Mathematica, vol. 13, pp. 55–62, 2002.
  109. L. Székelyhidi, The Octahedron and Cube Functional Equations Revisited, Publ. Math. Debrecen, vol. 61(3–4), pp. 241–252, 2002.
  110. P. Sahoo and L. Székelyhidi, A Functional Equation on ZnxYm, Acta Math. Hung., vol. 94(1–2), pp. 93–98, 2002.
  111. L. Székelyhidi, On discrete spectral synthesis, in Functional Equations – Results and Advances (Z. Daróczy and Z. Páles, eds.), pp. 263–274, Boston, Dordrecht, London: Kluwer Academic Publishers, 2002.
  112. P. Sahoo and L. Székelyhidi, On a Functional Equation Related to Digital Filtering, Aequationes Math., vol. 62, pp. 280–285, 2001.
  113. L. Székelyhidi, A Wiener Tauberian theorem on discrete abelian torsion groups, Annales Acad. Paedag. Cracov., Studia Mathematica I., vol. 4, pp. 147–150, 2001.
  114. L. Székelyhidi, Convolution–type functional equations, (in Hungarian) in Közgyűlési Előadások, pp. 451–456, Hungarian Academy of Sciences, May, 2000.
  115. L. Székelyhidi, Ulam’s problem, Hyers’s solution -and to where they led, in Stability of functional equations (T. M. Rassias, ed.), pp. 259–285, Boston, Dordrecht, London: Kluwer Academic Publishers, 2000.
  116. L. Székelyhidi, On the extension of exponential polynomials, Math. Bohemica, vol. 125(3), pp. 365–370, 2000.
  117. L. Székelyhidi, On a wave–type functional equation, in Advances in Equations and Inequalities (J. M. Rassias, ed.), pp. 219–224, Palm Harbor, USA: Hadronic Press, 1999.
  118. L. Székelyhidi, On convolution type functional equations, Math. Pannonica, vol. 10(2), pp. 271–275, 1999.
  119. L. Székelyhidi, On mean periodic functions, Aequationes Math., vol. 58(3), pp. 203–213, 1999.
  120. R. Badora, Z. Páles, and L. Székelyhidi, Monomial Selections of Set-valued Mappings, Aequationes Math., vol. 58(1–2), pp. 214–222, 1999.
  121. L. Székelyhidi, Laudation for Zoltán Daróczy, in Leaflets in Mathematics (Pécs, Hungary) (Z. Páles, ed.), Pécs, Hungary: Janus Pannonius University, 1998.
  122. L. Székelyhidi, On common eigenfunctions of difference operators, Publ. Math. Debrecen, vol. 52(3–4), pp. 699–704, 1998.
  123. L. Székelyhidi, Cosine operator functions on inner product spaces, in Inner product spaces and applications (Harlow), Pitman Research Notes in Mathematics Series, pp. 266–269, Harlow: Longman, 1997.
  124. L. Székelyhidi, On a characterization of linear operators, Acta Math. Hungar., vol. 71(4), pp. 293–295, 1996.
  125. A. Járai and L. Székelyhidi, Regularization and general methods in the theory of functional equations, Aequationes Math., vol. 52(1–2), pp. 10– 29, 1996.
  126. L. Székelyhidi, Functional equations via spectral synthesis, in Leaflets in Mathematics, Pécs, Hungary: Janus Pannonius University, 1995.
  127. L. Székelyhidi, Stability problems of functional equations in several variables, Publ. Math. Debrecen, vol. 47(1–2), pp. 95–100, 1995.
  128. L. Székelyhidi, On a characterization of linear operators, in Stability of mappings of Hyers-Ulam type (Palm Harbor, FL) (T. M. Rassias and J. Tabor, eds.), pp. 153–156, Palm Harbor, FL, USA: Hadronic Press, 1994.
  129. L. Székelyhidi, The stability of homogeneous functions, J. Univ. Kuwait Sci., vol. 20, pp. 159–164, 1993.
  130. L. Székelyhidi, Mean value-type functional equations, Aequationes Math., vol. 42(1), pp. 23–36, 1991.
  131. L. Székelyhidi, Summing power series with exponential polynomial coefficients, Publ. Math. Debrecen, vol. 38(3–4), pp. 245–246, 1991.
  132. L. Székelyhidi, The stability of the sine and cosine equations, Proc. Amer. Math. Soc., vol. 110(1), pp. 109–115, 1990.
  133. L. Székelyhidi, Stability properties of functional equations describing the scientific laws, Jour. Math. Anal. Appl., vol. 150(1), pp. 151–158, 1990.
  134. L. Székelyhidi, An abstract superstability theorem, Abh. Math. Sem. Univ. Hamburg, vol. 59, pp. 81–83, 1989.
  135. L. Székelyhidi, On a problem of S.Mazur, Trans. Amer. Math. Soc., vol. 316(1), pp. 161–164, 1989.
  136. L. Székelyhidi, Note on polynomial mappings, Publ. Math. Debrecen, vol. 36, pp. 263–265, 1989.
  137. L. Székelyhidi, On a linear functional equation, Aequationes Math., vol. 38, pp. 73–85, 1989.
  138. L. Székelyhidi, On the Levi–Civitá functional equation, Forschungszentrum Graz, Mathematisch–Statistische Sektion, Graz, vol. 301, 1988.
  139. L. Székelyhidi, Stability of some functional equations in economics, Rend. Sem. Mat. Fis. Milano, vol. 58, pp. 169–176, 1988.
  140. L. Székelyhidi, Fréchet equation and Hyers’s theorem on noncommutative semigroups, Ann. Polon. Math., vol. 448, pp. 183–189, 1988.
  141. G. Maksa, G. Szabó, and L. Székelyhidi, Equations arising from the theory of orthogonally additive and quadratic functions, C. R. Math. Rep. Acad. Sci. Canada, vol. 10(6), pp. 295–300, 1988.
  142. L. Székelyhidi, On addition theorems, C. R. Math. Rep. Acad. Sci. Canada, vol. 9(3), pp. 139–141, 1987.
  143. L. Székelyhidi, Remarks on Hyers’s theorem, Publ. Math. Debrecen, vol. 34(1–2), pp. 131–135, 1987.
  144. L. Székelyhidi, Lp-approximation by splines, Ann. Univ. Sci. Budapest, Sect. Comp., vol. 7, pp. 33–40, 1987.
  145. L. Székelyhidi, The Fourier transform of mean periodic functions, Util. Math., vol. 29, pp. 43–48, 1986.
  146. L. Székelyhidi, Note on Hyers’s theorem, C. R. Math. Rep. Acad. Sci. Canada, vol. 8(2), pp. 127–129, 1986.
  147. L. Székelyhidi, The Fourier transform of exponential polynomials, Publ. Math. Debrecen, vol. 33(1–2), pp. 13–20, 1986.
  148. L. Székelyhidi, Exponential polynomials and differential equations, Publ. Math. Debrecen, vol. 32, pp. 105–109, 1985.
  149. L. Székelyhidi, A characterization of trigonometric polynomials, C. R. Math. Rep. Acad. Sci. Canada, vol. 7(5), pp. 315–320, 1985.
  150. L. Székelyhidi, Regularity properties of exponential polynomials on groups, Acta Math. Acad. Sci. Hung., vol. 45(1–2), pp. 21–26, 1985.
  151. L. Székelyhidi, Regularity properties of polynomials on groups, Acta Math. Acad. Sci. Hung., vol. 45(1–2), pp. 15–19, 1985.
  152. L. Székelyhidi, Lp-approximation by splines, in Constructive Theory of Functions ’84, pp. 853–859, 1984.
  153. L. Székelyhidi, Local polynomials and functional equations, Publ. Math. Debrecen, vol. 30, pp. 283–290, 1983.
  154. L. Székelyhidi, Almost periodicity and functional equations, Aequationes Math., vol. 26, pp. 163–175, 1983.
  155. L. Székelyhidi, Remark 17., Aequationes Math., vol. 29, 1985.
  156. L. Székelyhidi, The stability of d’Alembert–type functional equations, Acta Sci. Math. Szeged, vol. 44, pp. 313–320, 1982.
  157. L. Székelyhidi, On the zeros of exponential polynomials, C. R. Math. Rep. Acad. Sci. Canada, vol. 4(4), pp. 189–194, 1982.
  158. L. Székelyhidi, Note on a stability theorem, Canadian Math. Bull., vol. 25(4), pp. 500–501, 1982.
  159. L. Székelyhidi, Note on exponential polynomials, Pacific J. Math., vol. 103(2), pp. 583–587, 1982.
  160. L. Székelyhidi, On a class of linear functional equations, Publ. Math. Debrecen, vol. 29, pp. 19–28, 1982.
  161. L. Székelyhidi, On a theorem of Baker, Lawrence and Zorzitto, Proc. Amer. Math. Soc., vol. 84, pp. 95–96, 1982.
  162. L. Székelyhidi, Exponential Polynomials and Functional Equations on Topological Groups, 1982. CSc Thesis.
  163. M. Lénárd and L. Székelyhidi, Functional-differential equations by spline functions, Ann. Univ. Sci. Budapest, Sect. Comput., vol. 3, pp. 25–32, 1982.
  164. M. Lénárd and L. Székelyhidi, Functional-differential equations by spline functions, pp. 433–436, Rousse, Bulgaria: Techn. Univ. Rousse, 1982.
  165. L. Székelyhidi, Functional equations on abelian groups, Acta Math. Acad. Sci. Hung., vol. 37, pp. 235–243, 1981.
  166. L. Székelyhidi, An extension theorem for a functional equation, Publ. Math. Debrecen, vol. 28, pp. 257–279, 1981.
  167. L. Székelyhidi, On a stability theorem, C. R. Math. Rep. Acad. Sci. Canada, vol. 3(5), pp. 253–255, 1981.
  168. L. Székelyhidi, The stability of linear functional equations, C. R. Math. Rep. Acad. Sci. Canada, vol. 3(2), pp. 63–67, 1981.
  169. L. Székelyhidi, Almost periodic functions and functional equations, Acta Sci. Math. Szeged, vol. 42, pp. 165–169, 1980.
  170. L. Székelyhidi, Remark on a paper of M. A. McKiernan, Ann. Polon. Math., vol. 36, pp. 245–247, 1979.
  171. L. Székelyhidi, On a Class of Linear Functional Equations, (in Hungarian), 1978. PhD Thesis.
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