Fechner, Ż., Gselmann, E., Székelyhidi, L.: Endomorphisms and derivations of the measure algebra of commutative hypergroups.
Indag. Math.-New Ser. [Epub ahead of print] (-), -, 2023.

Székelyhidi, L.: Finite dimensional varieties over the Heisenberg group.
Aequ. Math. 97 (2), 377-390, 2023.

Fechner, Ż., Gselmann, E., Székelyhidi, L.: Generalized derivations and generalized exponential monomials on hypergroups.
Opuscula math. 43 (4), 493-505, 2023.

Fechner, Ż., Gselmann, E., Székelyhidi, L.: Moment functions of higher rank on some types of hypergroups.
Semigr. Forum. 107 (3), 624-636, 2023.

Abayomi, E., Ali, A., Bessenyei, M., Boros, Z., Chmielewska, K., Chudziak, J., Gát, G., Gilányi, A., Grünwald, R., Gselmann, E., Iqbal, M., Kiss, T., Łukasik, R., Maslyuchenko, O., Menzer, R., Molnár, G., Olbryś, A., Páles, Z., Pénzes, E., Pieszczek, M., Sablik, M., Székelyhidi, L., Szostok, T., Tóth, N., Tóth, P., Wójcik, S., Zürcher, T.: Report of Meeting: The Twenty-second Debrecen-Katowice Winter Seminar on Functional Equations and Inequalities Hajdúszoboszló (Hungary), February 1-4, 2023.
Ann. Math. Sil. 37 (2), 315-334, 2023.

Adamek, M., Ali, A., Baias, A., Bessenyei, M., Boros, Z., Gilányi, A., Grünwald, R., Gselmann, E., Iqbal, M., Kiss, T., Kiss, G., Menzer, R., Nagy, G., Páles, Z., Székelyhidi, L., Szokol, P., To, L., Tóth, P., Tóth, N.: The 59th International Symposium on Functional Equations Hotel Aurum, Hajdúszoboszló (Hungary), June 18-25, 2023.
Aequ. Math. 97 (5-6), 1259-1290, 2023.

Fechner, Ż., Gselmann, E., Székelyhidi, L.: Moment functions of higher rank on polynomial hypergroups.
Adv. Oper. Theory. 7 (3), 1-9, 2022.

Fechner, Ż., Gselmann, E., Székelyhidi, L.: Spectral synthesis via moment functions on hypergroups.
Forum Math. 34 (5), 1187-1197, 2022.

Székelyhidi, L., Fechner, Ż.: Finite dimensional varieties on hypergroups.
Aequ. Math. 95 (3), 551-567, 2021.

Fechner, Ż., Gselmann, E., Székelyhidi, L.: Moment functions and exponential monomials on commutative hypergroups.
Aequ. Math. 95 1281-1290, 2021.

Fechner, Ż., Gselmann, E., Székelyhidi, L.: Moment Functions on Groups.
Results Math. 76 (4), 1-16, 2021.

Gselmann, E., Székelyhidi, L.: Symmetric spectral synthesis.
Aequ. Math. 95 (2), 255-279, 2021.

Vati, K., Székelyhidi, L.: Exponential monomials on hypergroup joins.
Miskolc Math. Notes. 21 (1), 463-472, 2020.

Żywilla, F., Székelyhidi, L.: Remarks on infinite hypergroup joins.
Ann. Univ. Sci. Bp. Rolando Eötvös Nomin., Sect. comput. 51 89-95, 2020.

Székelyhidi, L.: Spectral synthesis and partial differential equations.
Acta Math. Hung. 161 (1), 31-47, 2020.

Fechner, Ż., Székelyhidi, L.: Functional equations for exponential polynomials.
Aequ. Math. 93 (3), 535-545, 2019.

Fechner, Ż., Székelyhidi, L.: Moment Functions on Affine Groups.
Results Math. 74 (1), 1-13, 2019.

Vati, K., Székelyhidi, L.: Moment functions on hypergroup joins.
Advances in Pure and Applied Mathematics 10 (3), 215-220, 2019.

Székelyhidi, L.: Note on the semi-simplicity of measure algebras.
Monatsh. Math. 192 (4), 935-938, 2019.

Székelyhidi, L.: Spectral synthesis on the affine group of SU(n).
Acta math. Hung. 158 (2), 352-362, 2019.

Fechner, Ż., Székelyhidi, L.: Spherical and moment functions on the affine group of SU(n).
Acta math. Hung. 157 (1), 10-26, 2019.

Székelyhidi, L., Kedumetse, V.: Functional equations on hypergroup joins.
Arch. Math. 109 (1), 41-47, 2017.

Székelyhidi, L.: Invariant means on double coset spaces.
Period. Math. Hung. 75 (1), 58-65, 2017.

Fechner, Ż., Székelyhidi, L.: A generalization of Gajda's equation on commutative topological groups.
Publ. Math. Debr. 88 (1-2), 163-176, 2016.

Székelyhidi, L.: Annihilator methods for spectral synthesis on locally compact Abelian groups.
Monatsh. Math. 180 (2), 357-371, 2016.

Almira, J., Székelyhidi, L.: Characterization of Classes of Polynomial Functions.
Mediterr. J. Math. 13 (1), 301-307, 2016.

Almira, J., Székelyhidi, L.: Erratum to: On the Closure of Translation-Dilation Invariant Linear Spaces of Polynomials.
Results Math. 69 (1-2), 273-274, 2016.

Almira, J., Székelyhidi, L.: Montel-Type Theorems for Exponential Polynomials.
Demonstr. Math. 49 (2), 197-212, 2016.

Almira, J., Székelyhidi, L.: On the Closure of Translation-Dilation Invariant Linear Spaces of Polynomials.
Results Math. 69 (1-2), 263-272, 2016.

Székelyhidi, L.: On the principal ideal theorem and spectral synthesis on discrete Abelian groups.
Acta math. Hung. 150 (1), 228-233, 2016.

Székelyhidi, L.: Remark on the graph of additive functions.
Aequ. Math. 90 (1), 7-9, 2016.

Fechner, Ż., Székelyhidi, L.: Sine functions on hypergroups.
Arch. Math. 106 (4), 371-382, 2016.

Székelyhidi, L., Wilkens, B.: Spectral analysis and synthesis on varieties.
J. Math. Anal. Appl. 433 (2), 1329-1332, 2016.

Székelyhidi, L., Vajday, L.: Spectral synthesis on commutative hypergroups.
Annales Univ. Sci. Budapest., Sect. Comp. 45 111-117, 2016.

Székelyhidi, L.: A functional equation for exponential polynomials.
Aequ. Math. 89 (3), 821-828, 2015.

Almira, J., Székelyhidi, L.: Local polynomials and the Montel theorem.
Aequ. Math. 89 (2), 329-338, 2015.

Székelyhidi, L.: Stability of functional equations on hypergroups.
Aequ. Math. 89 (6), 1475-1483, 2015.

Székelyhidi, L.: Annihilator Methods in Discrete Spectral Synthesis.
Acta math. Hung. 143 (2), 351-366, 2014.

Horváth, G., Székelyhidi, L., Wilkens, B.: Non-synthesizable varieties.
J. Math. Anal. Appl. 417 (1), 394-399, 2014.

Székelyhidi, L.: On Fréchet's functional equation.
Monatsh. Math. 175 (4), 639-643, 2014.

Székelyhidi, L.: A characterization of exponential polynomials.
Publ. Math.-Debr. 83 (4), 757-771, 2013.

Székelyhidi, L.: Exponential polynomials on commutative hypergroups.
Arch. Math. 101 (4), 341-347, 2013.

Székelyhidi, L.: Functional Equations on Hypergroups.
World Scientific, Singapore ;, xvii, 191 p., 2013. ISBN: 9789814407007

Páles, Z., Székelyhidi, L.: Laudation to Zoltán Daróczy.
Annales Univ. Sci. Budapest., Sect. Comp. 40 9-20, 2013.

Székelyhidi, L., Vajday, L.: On conditional functional equations with applications on hypergroups.
Annales Univ. Sci. Budapest., Sect. Comp. 41 323-332, 2013.

Székelyhidi, L.: Spectral synthesis problems on hypergroups.
Annales Univ. Sci. Budapest., Sect. Comp. 39 439-447, 2013.

Székelyhidi, L.: The Levi-Civita equation, vector modules and spectral synthesis.
In: Recent Developments in Functional Equations and Inequalities. Ed.: Janusz Brzdęk, Jacek Chmieliński, Krzysztof Ciepliński, Roman Ger, Zsolt Páles, Marek Cezary Zdun, Banach Center Publications, Warsaw, 193-206, 2013, (Banach Center Publications, ISSN 0137-6934 ; 99.) ISBN: 9788386806188

Székelyhidi, L., Vajday, L.: A moment problem on some types of hypergroups.
Ann. Funct. Anal. 3 (2), 58-65, 2012.

Székelyhidi, L., Vajday, L.: Functional equations on the SU(2)-hypergroup.
Math. Pannon. 23 (2), 187-193, 2012.

Székelyhidi, L.: Noetherian rings of polynomial functions on Abelian groups.
Aequ. Math. 84 (1-2), 41-50, 2012.

Székelyhidi, L.: Polynomial functions and spectral synthesis on Abelian groups.
Banach J. Math. Anal. 6 (1), 124-131, 2012.

Székelyhidi, L., Vajday, L.: Spectral analysis and moment functions.
J. Inform. Math. Sci. 4 (2), 185-188, 2012.

Székelyhidi, L.: Spectral analysis and spectral synthesis.
In: Nonlinear analysis : Stability, Approximation, and Inequalities. Eds.: Panos M. Pardalos, Pando G. Georgiev. Hari M. Srivastava, Springer, New York, 707-719, 2012. ISBN: 9781461434979

Székelyhidi, L.: Fourier transform for mean periodic functi.
Ann. Univ. Sci. Budapest. Sect. Comput. 35 267-284, 2011.

Székelyhidi, L.: Fourier transform for mean periodic functions.
Ann. Univ. Sci. Bp. Rolando Eötvös Nomin., Sect. comput. 35 267-283, 2011.

Székelyhidi, L., Vajday, L.: Spectral analysis on commutative hypergroups.
Aequ. Math 80 (1-2), 223-226, 2010.

Székelyhidi, L.: Spectral synthesis problems on locally compact groups.
Monatsh. Math. 161 (2), 223-232, 2010.

Orosz, Á., Székelyhidi, L.: Moment functions on Sturm-Liouville hypergroups.
Annales Univ. Sci. Sec. Comp. 29 141-156, 2008.

Székelyhidi, L.: Spectral synthesis on multivariate polynomial hypergroups.
Monatsh. Math. 153 (2), 145-152, 2008.

Székelyhidi, L.: D'Alembert's functional equation on compact groups.
Banach J. Math. Anal. 1 (2), 221-226, 2007.

Laczkovich, M., Székelyhidi, L.: Spectral synthesis on discrete Abelian groups.
Math. Proc. Cambridge Phil. Soc. 143 (1), 103-120, 2007.

Székelyhidi, L.: Functional equations on Sturm-Liouville hypergroups.
Math. Pannon. 17 (2), 169-182, 2006.

Moslehian, M., Székelyhidi, L.: Stability of Ternary Homomorphisms via Generalized Jensen Equation.
Results Math. 49 (3-4), 289-300, 2006.

Székelyhidi, L.: Discrete spectral synthesis.
Ann. Math. Inform. 32 141-152, 2005.

Orosz, Á., Székelyhidi, L.: Moment functions on polynomial hypergroups.
Arch. Math. 85 (2), 141-150, 2005.

Ebanks, B., Székelyhidi, L.: On multiplicative and additive differences.
Aequ. Math. 69 (1-2), 97-113, 2005.

Székelyhidi, L.: Polynomial functions and spectral synthesis.
Aequ. Math. 70 (1-2), 122-130, 2005.

Székelyhidi, L.: Spectral synthesis and a characterization of polynomial ideals.
Publ. Math. Debr. 66 (1-2), 183-195, 2005.

Bereczky, Á., Székelyhidi, L.: Spectral synthesis on torsion groups.
J. Math. Anal. Appl. 304 (2), 607-613, 2005.

Székelyhidi, L.: Difference equations via spectral synthesis.
Annales Univ. Sci. Budapest., Sect. Comp. 24 3-14, 2004.

Páles, Z., Székelyhidi, L.: On approximate sandwich and decomposition theorems.
Ann. Univ. Sci. Budapest. Sect. Comput. 23 59-70, 2004.

Chung, J., Sahoo, P., Székelyhidi, L.: On quadratic differences that depend on the product of arguments: revisited.
Aequ. Math. 67 (3), 216-224, 2004.

Székelyhidi, L.: Spectral Analysis and Spectral Synthesis on Polynomial Hypergroups.
Monatsh. Math. 141 (1), 33-43, 2004.

Székelyhidi, L.: The failure of spectral synthesis on some types of?discrete Abelian groups.
J. Math. Anal. Appl. 291 (2), 757-763, 2004.

Sahoo, P., Székelyhidi, L.: On the general solution of a functional equation on Z+Z.
Arch. Math. 81 (2), 233-239, 2003.

Sahoo, P., Székelyhidi, L.: A functional equation on Zn + Zn.
Acta Math. Hung. 94 (1-2), 93-98, 2002.

Székelyhidi, L.: On a paper of T. M. K. Davison.
Ann. Univ. Paedag. Cracoviensis. Studia Math. 13 55-62, 2002.

Székelyhidi, L.: On Discrete Spectral Synthesis.
In: Functional Equations : Results and Advances. Ed.: Zoltán Daróczy, Zsolt Páles, Springer, Boston, 263-274, 2002, (Advances in Mathematics ; 3.) ISBN: 9781441952103

Székelyhidi, L.: The octahedron and cube functional equations revisited.
Publ. Math. Debr. 61 (3-4), 241-252, 2002.

Székelyhidi, L.: A Wiener Tauberian theorem on discrete abelian torsion groups.
Annales Academiae Paedagigicae Cracoviensis: Studia Mathematica 4 147-150, 2001.

Sahoo, P., Székelyhidi, L.: On a functional equation related to digital filtering.
Aequ. Math. 62 (3), 280-285, 2001.

Székelyhidi, L.: On the extension of exponential polynomials.
Math. Bohemica. 125 (3), 365-370, 2000.

Székelyhidi, L.: Ulam's problem, Hyers's solution and to where they led.
In: Functional equations and inequalities. Ed.: Themistocles M. Rassias, Springer, Dordrecht, 259-285, 2000, (Mathematics and Its Applications; 518.) ISBN: 9780792364849

Badora, R., Páles, Z., Székelyhidi, L.: Monomial selections of set-valued maps.
Aequ. Math. 58 (3), 214-222, 1999.

Székelyhidi, L.: On convolution type functional equations.
Math. Pannon. 10 (2), 271-275, 1999.

Székelyhidi, L.: On mean periodic functions.
Aequ. Math. 58 (3), 203-213, 1999.

Székelyhidi, L.: Valószínűségszámítás és matematikai statisztika.
EKTF Líceum Kiadó, Eger, 152 p., 1999.

Székelyhidi, L.: Laudatio to professor Daróczy.

Székelyhidi, L.: On common eigenfunctions of difference operators.
Publ. Math. Debrecen. 52 699-704, 1998.

Székelyhidi, L.: Cosine operator functions on inner product spaces.

Székelyhidi, L.: On a characterization of linear operators.

Székelyhidi, L.: On a characterization of linear operators.

Székelyhidi, L.: On cosine operator functions.
Grazer Math. Ber. 327 59-60, 1996.

Járai, A., Székelyhidi, L.: Regularization and general methods in the theory of functional equations.
Aequ. Math. 52 (1), 10-29, 1996.

Székelyhidi, L.: Stability properties of functional equations in several variables.
Publ. Math. Debrecen. 47 (1-2), 95-100, 1995.

Székelyhidi, L.: Stability properties of functional equations describing the scientific laws.
J. Math. Anal. Appl. 150 (1), 151-158, 1990.

Székelyhidi, L.: An abstract superstability theorem.
Abh. Math. Semin. Univ. Hamburg. 59 (1), 81-83, 1989.

Székelyhidi, L., Szabó, G., Maksa, G.: Equations arising from the theory of orthogonally additive and quadratic functions.
Math. reports Acad. Sci. Canada 10 (6), 295-300, 1989.

Székelyhidi, L.: On a linear functional equation.
Aequ. Math. 38 (2-3), 113-122, 1989.

Székelyhidi, L., LÉNÁRD, M.: Spline approximation method for the wave equation..
Bull. Appl. Math 1989.

Székelyhidi, L.: Stability of some functional equations in economics.
Rend. Semin. Mat. Fis. Milan. 58 (1), 169-176, 1988.

Székelyhidi, L.: Note on Hyers's theorem.
C. R. Math. Rep. Acad. Sci. Canada. 8 (2), 127-129, 1986.

Székelyhidi, L.: The Fouries transform of exponential polynomials.
Publ. Math. 33 13-20, 1986.

Székelyhidi, L.: The Fouries transform of mean periodic functions.
Utilitas Math. 29 43-48, 1986.

Székelyhidi, L.: Exponential polynomials and differential equations.
Publ. Math. Debr. 32 (1-2), 105-109, 1985.

Székelyhidi, L., Székelyhidi, L.: Hans Triebel: Theory of function spaces.
Publ. Math. Debrecen. 32 306, 1985.
(Ismertetett mű: Hans Triebel. -Theory of function spaces /Leipzig : Akad. Verlag, 1983. -284 p. -)

Székelyhidi, L.: Ismertetés: Lectures on partial differential equations.
Publ. Math. Debrecen. 32 283, 1985.
(Ismertetett mű: by G.B. Folland ; notes by K.T. Joseph and S. Thangavelu. -Lectures on partial differential equations /New Delhi : Published for the Tata Institute of Fundamental Research, Bombay, [by] Narosa Pub. House, 1983. -ii, 160 p. -)

Székelyhidi, L.: Ismertetés: Selecta :.
Publ. Math. Debrecen. 32 279, 1985.
(Ismertetett mű: P.R. Halmos ; edited by Donald E. Sarason, Leonard Gillman. -Selecta : expository writing /New York ; Heidelberg : Springer-Verlag, 1983. -XIX, 304 p.)

Székelyhidi, L.: Ismertetés: Theorems and problems in functional analysis.
Publ. Math. Debrecen. 32 281, 1985.
(Ismertetett mű: A. A. Kirillov, A. D. Gvishiani ; translated by Harold H. McFaden. -Theorems and problems in functional analysis /New York : Springer-Verlag, c1982. -ix, 347 p. -)

Székelyhidi, L.: R. E. Edwards: Fourier series: a modern introduction., Vol. 2..
Publ. Math. Debrecen. 32 280-281, 1985.
(Ismertetett mű: R. E. Edwards. -Fourier series : a modern introduction., Vol. 2. /New York ; Heidelberg : Springer-Verlag, 1982. -)

Székelyhidi, L.: Almost periodicity and functional equations.
Aequ. Math. 26 (1), 163-175, 1983.