**Hasil Penelitian 2020**:

M. Nur and H. Gunawan*, A note on the g-angle between subspaces of a normed space, submitted (*supported by RIK-A ITB)

S. Rante, A. Adam, and H. Gunawan*, On inner products derived from the standard *n*-inner product on an inner product space, submitted (*supported by RIK-A ITB)

I. Sihwaningrum, S. Maryani, and H. Gunawan*, Extensions of Hardy-Littlewood-Sobolev inequalities for Riesz potentials on hypergroups, submitted (*supported by P3MI ITB)

H. Gunawan*, D.I. Hakim, and A.S. Putri*, On geometric properties of Morrey spaces, submitted (*supported by P3MI ITB)

H. Rahman and H. Gunawan*, Generalized Von Neumann-Jordan constant for Morrey spaces and small Morrey spaces, submitted (*supported by RIK-A ITB)

**Hasil Penelitian 2019:**

H. Gunawan, E. Kikianty, Y. Sawano, and C. Schwanke, Three geometric constants for Morrey spaces, Bull. Korean Math. Soc.

N.K. Tumalun, D.I. Hakim, and H. Gunawan, Fefferman’s inequality and unique continuation property of elliptic partial differential equations, submitted

H. Batkunde and H. Gunawan, Bounded linear functional on *n*-normed spaces through its quotient spaces, Internat. J. Appl. Phys. Math.

H. Batkunde and H. Gunawan, A revisit to *n*-normed spaces through its quotient spaces, Mat. Stud.

M. Nur and H. Gunawan, Three equivalent n-norms on the space of *p*-summable sequences, Fundam. J. Math. Appl.

***

**Periode 2016-2020:**

2016: A new 2-inner product on the space of *p*-summable sequences (with S. Konca and M. Idris)

2016: The boundedness of Bessel-Riesz operators on Morrey spaces (with M. Idris, J. Lindiarni, and Eridani)

2016: The boundedness of Bessel-Riesz operators on generalized Morrey spaces (with M. Idris and Eridani)

2016: Inclusion properties of Orlicz and weak Orlicz spaces (with A.A. Masta and W. Setya-Budhi)

2017: On the Fundamental Theorem of Arithmetic and Euclid’s Theorem

2017: The boundedness of generalized Bessel-Riesz operators on generalized Morrey spaces (with M. Idris)

2017: Inclusion properties of generalized Morrey spaces (with D.I. Hakim, K.M. Limanta, and A.A. Masta)

2017: An inclusion property of Orlicz-Morrey spaces (with A.A. Masta and W. Setya-Budhi)

2017: On inclusion properties of two versions of Orlicz-Morrey spaces (with A.A. Masta and W. Setya-Budhi)

2018: *n*-Normed spaces with norms of its quotient spaces (with H. Batkunde)

2018: Discrete Morrey spaces and their inclusion properties (with E. Kikianty and C. Schwanke)

2018: On inclusion relation between weak Morrey spaces and Morrey spaces (with D.I. Hakim, E. Nakai, and Y. Sawano)

2018: The Hardy and Heisenberg inequalities in Morrey spaces (with D.I. Hakim, E. Nakai, and Y. Sawano)

2018: Proper inclusion of Morrey spaces (with D.I. Hakim and M. Idris)

2018: A formula for the *g*-angle between two subspaces of a normed space (with M. Nur and O. Neswan)

2018: Generalized Holder’s inequality in Morrey spaces (with Ifronika, M. Idris, and A.A. Masta)

2018: Norm estimates for Bessel-Riesz operators on generalized Morrey spaces (with M. Idris)

2018: A new orthogonality and angle in a normed space (with M. Nur)

2019: Konsep garis singgung pada kurva (with V. Deviantri)

2019: The Hardy-Littlewood maximal operators on discrete Morrey spaces (with C. Schwanke)

2020: Inclusion between generalized Stummel classes and other function spaces (with N.K. Tumalun and D.I. Hakim)

***

**Periode 2011-2015:**

2011: On the product of *N* Chebyshev systems (with L. Ambarwati)

2011: Surfaces with prescribed nodes and minimum energy integral of fractional order (with E. Rusyaman and L. Ambarwati)

2011: Application of Reproducing Kernel Hilbert Spaces to a minimization problem with prescribed nodes (with Y. Sawano)

2012: Weak type inequalities for fractional integral operators on generalized non-homogeneous Morrey spaces (with I. Sihwaningrum and S. Maryani)

2012: A characterization for fractional integral operators on generalized Morrey spaces (with Eridani and M.I. Utoyo)

2012: Generalized Stummel class and Morrey spaces (with E. Nakai, Y. Sawano, and H. Tanaka)

2013: On the space of *p*-summable sequences (with M. Idris and S. Ekariani)

2013: The local trace inequality for potential type integral operators (with H. Tanaka)

2013: Two equivalent *n*-norms on the space of *p*-summable sequences (with R.A. Wibawa-Kusumah)

2013: Equivalence relations of *n*-norms on a vector space (with T.R. Kristianto and R.A. Wibawa-Kusumah)

2013: A contractive mapping theorem on the *n*-normed space of *p*-summable sequences (with S. Ekariani and M. Idris)

2013: Bounded linear functionals on the *n*-normed space of *p*-summable sequences (with H. Batkunde and Y.E.P. Pangalela)

2013: The *n*-dual space of the space of *p*-summable sequences (with Y.E.P. Pangalela)

2013: Multilinear maximal functions and fractional integrals on generalized Morrey spaces (with I. Sihwaningrum)

2013: Weak (*p*,*q*) inequalites for fractional integral operators on generalized Morrey spaces of non-homogeneous type (with D.I. Hakim)

2013: Weak type inequalities for some integral operators on generalized nonhomogeneous Morrey spaces (with D.I. Hakim, Y. Sawano, and I. Sihwaningrum)

2014: Characterizations for the gereralized fractional integral operators on Morrey spaces (with Eridani, E. Nakai, and Y. Sawano)

2014: Morrey spaces and Related Function Spaces (with Y. Sawano, V. Guliyev, and H. Tanaka)

2014: Some remarks on *l^p* as an *n*-normed space (with S. Konca and M. Basarir)

2015: *p*-summable sequence spaces with inner products (with S. Konca and M. Idris)

2015: *p*-summable sequence spaces with 2-inner products (with S. Konca, M. Idris, and M. Basarir)

2015: On the *n*-normed space of *p*-integrable functions (with S. Ekariani and M. Idris)

2015: Weak type inequalities for some operators on generalized Morrey spaces over metric measure spaces (with I. Sihwaningrum and A. Wardayani)

2015: Non-smooth atomic decomposition for generalized Orlicz-Morrey spaces (with Y. Sawano and D.I. Hakim)

2015: Fixed point theorems on bounded sets in an *n*-normed spaces (with E. Sukaesih and O. Neswan)

2015: A partial solution to an open problem in *n*-normed spaces (with M. Idris and S. Konca)

***

**Periode 2006-2010:**

2006: Orthogonality in 2-normed spaces revisited (with Mashadi, S. Gemawati, N. Supiamin, and I. Sihwaningrum)

2006: Orthogonality in *n*-normed spaces (with E. Kikianty, Mashadi, S. Gemawati, and I. Sihwaningrum)

2007: On integrals arising from a Lie group contraction problem (with S. Gupta)

2008: P-, I-, g-, and D-angles in normed spaces (with J. Lindiarni and O. Neswan)

2008: An interpolation method that minimizes an energy integral of fractional order (with F. Pranolo and E. Rusyaman)

2009: Fractional integrals and generalized Olsen inequalities (with Eridani)

2009: Fractional integral operators in non-homogeneous spaces (with Y. Sawano and I. Sihwaningrum)

2010: Fractional integrals and Olsen inequalities on nonhomogeneous spaces (with I. Sihwaningrum and H.P. Suryawan)

2010: Equivalence of *n*-norms on the space of *p*-summable sequences (with A, Mutaqin)

2010: On *n*-norms and bounded *n*-linear functionals in a Hilbert space (with S.M. Gozali and O. Neswan)

2010: On *b*-orthogonality in 2-normed spaces (with S.M. Gozali)

***

**Periode 2001-2005**:

2001: On finite dimensional 2-normed spaces (with Mashadi)

2001: An inner product that makes a set of vectors orthonormal

2001: On *n*-normed spaces (with Mashadi)

2001: The space of *p*-summable sequences and its natual *n*-norm

2002: Some estimates for imaginary powers of Laplace operators

2002: Weighted estimates for fractional maximal functions related to spherical means (with M. Cowling and J. Garcia-Cuerva)

2002: Inner products on *n*-inner product spaces

2002: On convergence in *n*-inner product spaces

2002: A generalization of Bessel’s inequality and Parseval’s identity

2002: On *n*-inner products, *n*-norms, and the Cauchy-Schwarz inequality

2002: A note on Dragomir-Mcandrew’s trapezoid inequality

2003: A note on the generalized fractional integral operators

2003: On measures of central location

2004: On the behavior of the solution of the wave equation (with W. Setya-Budhi)

2004: On generalized fractional integral operators (with Eridani and E. Nakai)

2005: Stummel class and Morrey spaces (with Eridani)

2005: A formula for angles between subspaces of inner product spaces (with O. Neswan and W. Setya-Budhi)

2005: On angles between subspaces of inner product spaces (with O. Neswan)

2005: On volumes of *n*-dimensional parallelepipeds in *l^p* spaces (with W. Setya-Budhi, Mashadi, and S. Gemawati)

***

**Periode 1992-2000**:

1992: A generalization of maximal functions on compact semisimple Lie groups

1993: *L²*-estimates for some maximal functions

1996: On weighted estimates for Stein’s maximal function

1997: On finding the fundamental dominant weights of a root system

1998: Some weighted estimates for Stein’s maximal function

2000: On the triangle inequality for the standard 2-norm (with W. Setya-Budhi)

***

* Unpublished Papers*:

2016: On the fundamental theorem of arithmetic and Euclid’s theorem

2006: Orthogonality in *n*-normed spaces

**See also**: https://scholar.google.co.id/citations?user=U9ZCm_YAAAAJ&hl=id&oi=ao and http://itb.academia.edu/HendraGunawan