Academic literature on the topic 'Functional equation and inequality'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Functional equation and inequality.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Functional equation and inequality"

1

Adamek, Mirosław. "On two variable functional inequality and related functional equation." Mathematical Inequalities & Applications, no. 4 (2009): 799–804. http://dx.doi.org/10.7153/mia-12-63.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Lee, Yang-Hi, and Gwang Kim. "Generalized Hyers–Ulam Stability of the Additive Functional Equation." Axioms 8, no. 2 (2019): 76. http://dx.doi.org/10.3390/axioms8020076.

Full text
Abstract:
We will prove the generalized Hyers–Ulam stability and the hyperstability of the additive functional equation f(x1 + y1, x2 + y2, …, xn + yn) = f(x1, x2, … xn) + f(y1, y2, …, yn). By restricting the domain of a mapping f that satisfies the inequality condition used in the assumption part of the stability theorem, we partially generalize the results of the stability theorems of the additive function equations.
APA, Harvard, Vancouver, ISO, and other styles
3

Alsina, C., and J. L. Garcia-Roig. "On a functional equation related to the Ptolemaic inequality." Aequationes Mathematicae 34, no. 2-3 (1987): 298–303. http://dx.doi.org/10.1007/bf01830679.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Ng, C. T. "On a functional equation related to income inequality measures." Aequationes Mathematicae 28, no. 1 (1985): 161–69. http://dx.doi.org/10.1007/bf02189408.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Bingham, N. H., and A. J. Ostaszewski. "Cauchy’s functional equation and extensions: Goldie’s equation and inequality, the Gołąb–Schinzel equation and Beurling’s equation." Aequationes mathematicae 89, no. 5 (2015): 1293–310. http://dx.doi.org/10.1007/s00010-015-0350-6.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Chung, Jae-Young. "On a Stability of Logarithmic-Type Functional Equation in Schwartz Distributions." Abstract and Applied Analysis 2012 (2012): 1–15. http://dx.doi.org/10.1155/2012/435310.

Full text
Abstract:
We prove the Hyers-Ulam stability of the logarithmic functional equation of Heuvers and Kannappanf(x+y)-g(xy)-h(1/x+1/y)=0, x,y>0, in both classical and distributional senses. As a classical sense, the Hyers-Ulam stability of the inequality|f(x+y)-g(xy)-h(1/x+1/y)|≤ϵ, x,y>0will be proved, wheref,g,h:ℝ+→ℂ. As a distributional analogue of the above inequality, the stability of inequality∥u∘(x+y)-v∘(xy)-w∘(1/x+1/y)∥≤ϵwill be proved, whereu,v,w∈𝒟'(ℝ+)and∘denotes the pullback of distributions.
APA, Harvard, Vancouver, ISO, and other styles
7

Kamont, Zdzisław, and Adam Nadolski. "Functional Differential Inequalities with Unbounded Delay." gmj 12, no. 2 (2005): 237–54. http://dx.doi.org/10.1515/gmj.2005.237.

Full text
Abstract:
Abstract We prove that a function of several variables satisfying a functional differential inequality with unbounded delay can be estimated by a solution of a suitable initial problem for an ordinary functional differential equation. As a consequence of the comparison theorem we obtain a Perron-type uniqueness result and a result on continuous dependence of solutions on given functions for partial functional differential equations with unbounded delay. We consider classical solutions on the Haar pyramid.
APA, Harvard, Vancouver, ISO, and other styles
8

Chung, Jaeyoung, Chang-Kwon Choi, and Jongjin Kim. "Ulam-Hyers Stability of Trigonometric Functional Equation with Involution." Journal of Function Spaces 2015 (2015): 1–7. http://dx.doi.org/10.1155/2015/742648.

Full text
Abstract:
LetSandGbe a commutative semigroup and a commutative group, respectively,CandR+the sets of complex numbers and nonnegative real numbers, respectively, andσ:S→Sorσ:G→Gan involution. In this paper, we first investigate general solutions of the functional equationf(x+σy)=f(x)g(y)-g(x)f(y)for allx,y∈S, wheref,g:S→C. We then prove the Hyers-Ulam stability of the functional equation; that is, we study the functional inequality|f(x+σy)-f(x)g(y)+g(x)f(y)|≤ψ(y)for allx,y∈G, wheref,g:G→Candψ:G→R+.
APA, Harvard, Vancouver, ISO, and other styles
9

Kim, Hark-Mahn, and Yang-Hi Lee. "STABILITY OF FUNCTIONAL EQUATION AND INEQUALITY IN FUZZY NORMED SPACES." Journal of the Chungcheong Mathematical Society 26, no. 4 (2013): 707–21. http://dx.doi.org/10.14403/jcms.2013.26.4.707.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Fechner, Włodzimierz. "Stability of a functional inequality associated with the Jordan – von Neumann functional equation." Aequationes mathematicae 71, no. 1-2 (2006): 149–61. http://dx.doi.org/10.1007/s00010-005-2775-9.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Dissertations / Theses on the topic "Functional equation and inequality"

1

Pinto, Manuel. "Des inegalites fonctionnelles et leurs applications." Université Louis Pasteur (Strasbourg) (1971-2008), 1988. http://www.theses.fr/1988STR13097.

Full text
Abstract:
Etude du comportement asymptotique des solutions des equations differentielles non lineaires. Solution d'une inegalite du type de gronwall-bellman-bihari avec un nombre fini quelconque de non-linearites. Applications : recherche des solutions asymptotiques et asymptotiquement polynomiales, stabilite des h-systemes en variation soumise a des perturbations integrales; solutions bornees des equations differentielles dans un espace de banach et equilibre asymptotique. Version discrete et multivariable de l'inegalite fonctionnelle resolue
APA, Harvard, Vancouver, ISO, and other styles
2

Dvořáková, Stanislava. "The Qualitative and Numerical Analysis of Nonlinear Delay Differential Equations." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2011. http://www.nusl.cz/ntk/nusl-233952.

Full text
Abstract:
Disertační práce formuluje asymptotické odhady řešení tzv. sublineárních a superlineárních diferenciálních rovnic se zpožděním. V těchto odhadech vystupuje řešení pomocných funkcionálních rovnic a nerovností. Dále práce pojednává o kvalitativních vlastnostech diferenčních rovnic se zpožděním, které vznikly diskretizací studovaných diferenciálních rovnic. Pozornost je věnována souvislostem asympotického chování řešení rovnic ve spojitém a diskrétním tvaru, a to v obecném i v konkrétních případech. Studována je rovněž stabilita numerické diskretizace vycházející z $\theta$-metody. Práce obsahuje
APA, Harvard, Vancouver, ISO, and other styles
3

Biesdorf, João. "Mínimos locais de funcionais com dependência especial via Γ convergência: com e sem vínculo." Universidade Federal de São Carlos, 2011. https://repositorio.ufscar.br/handle/ufscar/5822.

Full text
Abstract:
Made available in DSpace on 2016-06-02T20:27:39Z (GMT). No. of bitstreams: 1 3744.pdf: 1323892 bytes, checksum: 71a7a7180d61db167b8cbec4db2bbe8b (MD5) Previous issue date: 2011-05-30<br>Universidade Federal de Sao Carlos<br>We address the question of existence of stationary stable solutions to a class of reaction-diffusion equations with spatial dependence in 2 and 3-dimensional bounded domains. The approach consists of proving the existence of local minimizer of the corres-ponding energy functional. For existence, it was enough to give sufficient conditions on the diffusion coefficient and
APA, Harvard, Vancouver, ISO, and other styles
4

Xie, Wenzheng. "A sharp inequality for Poisson's equation in arbitrary domains and its applications to Burgers' equation." Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/31859.

Full text
Abstract:
Let Ω be an arbitrary open set in IR³. Let || • || denote the L²(Ω) norm, and let [formula omitted] denote the completion of [formula omitted] in the Dirichlet norm || ∇•||. The pointwise bound [forumula omitted] is established for all functions [formula omitted] with Δ u є L² (Ω). The constant [formula omitted] is shown to be the best possible. Previously, inequalities of this type were proven only for bounded smooth domains or convex domains, with constants depending on the regularity of the boundary. A new method is employed to obtain this sharp inequality. The key idea is to estimat
APA, Harvard, Vancouver, ISO, and other styles
5

Wang, Xinyu. "Sur la convergence sous-exponentielle de processus de Markov." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2012. http://tel.archives-ouvertes.fr/tel-00840858.

Full text
Abstract:
Ma thèse de doctorat se concentre principalement sur le comportement en temps long des processus de Markov, les inégalités fonctionnelles et les techniques relatives. Plus spécifiquement, Je vais présenter les taux de convergence sous-exponentielle explicites des processus de Markov dans deux approches : la méthode Meyn-Tweedie et l'hypocoercivité (faible). Le document se divise en trois parties. Dans la première partie, Je vais présenter quelques résultats importants et des connaissances connexes. D'abord, un aperçu de mon domaine de recherche sera donné. La convergence exponentielle (ou sous
APA, Harvard, Vancouver, ISO, and other styles
6

Daquila, Richard. "Strongly annular solutions to Mahler's functional equation /." The Ohio State University, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487844948075255.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Torres, Ledezma Sebastián Generoso. "Institutions, inequality and the impact of foreign aid : a simultaneous equation approach." Thesis, University of Leicester, 2007. http://hdl.handle.net/2381/30158.

Full text
Abstract:
This study extends existing work on inequality, institutions and the impact of foreign aid by constructing and estimating different cross-country simultaneous equation models that identify bi-directional relationships between income inequality and several indicators of social and economic development. The first set of results for a model combining four endogenous variables (income, education, health and inequality) and estimated using the three-stage least-squares (3SLS) technique, show that lower inequality is associated with improvements in other development indicators, but this is the resul
APA, Harvard, Vancouver, ISO, and other styles
8

Laming, Gregory John. "Density functional theory for molecules." Thesis, University of Cambridge, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336907.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Acosta, Mesa Héctor Gabriel. "Functional anatomy of stereoscopic visual process assessed using functional magnetic resonance imaging and structural equation modelling." Thesis, University of Sheffield, 2003. http://etheses.whiterose.ac.uk/14748/.

Full text
Abstract:
The purpose of this thesis is to study the functional anatomy of stereoscopic vision. Although many studies have investigated the physiological mechanisms by which the brain transforms the retinal disparities into three-dimensional representations, the invasive nature of the techniques available have restricted them to studies in non-human primates, whilst the research on humans has been limited to psychophysical studies. Modem non-invasive neuroimaging techniques now allow the investigation of the functional organisation of the human brain. Although PET and fMRI studies have been widely used,
APA, Harvard, Vancouver, ISO, and other styles
10

Michels, Tara Marie. "Towards a connection between linear embedding and the Poincaré functional equation." [Johnson City, Tenn. : East Tennessee State University], 2003.

Find full text
Abstract:
Thesis (M.S.)--East Tennessee State University, 2003.<br>Title from electronic submission form. ETSU ETD database URN: etd-1109103-132618. Includes bibliographical references. Also available via Internet at the UMI web site.
APA, Harvard, Vancouver, ISO, and other styles

Books on the topic "Functional equation and inequality"

1

An introduction to the theory of functional equations and inequalities : Cauchy's equation and Jensen's inequality. Państwowe Wydawn. Naukowe, 1985.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
2

Attila, Gilányi, ed. An introduction to the theory of functional equations and inequalities: Cauchy's equation and Jensen's inequality. 2nd ed. Birkäeuser, 2009.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
3

Kuczma, Marek. An introduction to the theory of functional equations and inequalities: Cauchy's equation and Jensen's inequality. 2nd ed. Birkäeuser, 2009.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
4

Kuczma, Marek. An introduction to the theory of functional equations and inequalities: Cauchy's equation and Jensen's inequality. 2nd ed. Birkäeuser, 2009.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
5

Ugo, Gianazza, Vespri Vincenzo, and SpringerLink (Online service), eds. Harnack's Inequality for Degenerate and Singular Parabolic Equations. Springer Science+Business Media, LLC, 2012.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
6

Berezin, F. A. The Schrödinger Equation. Springer Netherlands, 1991.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
7

Roussel, Marc R. Functional equation methods in steady-state enzyme kinetics. National Library of Canada, 1990.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
8

P, Wittwer, ed. Computer methods and Borel summability applied to Feigenbaum's equation. Springer-Verlag, 1985.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
9

1942-, Zhao Zhongxin, ed. From Brownian motion to Schrödinger's Equation. Springer-Verlag, 1995.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
10

Kamuntavichi͡us, G. P. P. Ob ėkvivalentnosti uravnenii͡a shredingera dli͡a atomnogo i͡adra prostomu different͡sialʹno-funkt͡sionalʹnomu uravnenii͡u. Akademii͡a nauk Litovskoĭ SSR, In-t fiziki, 1985.

Find full text
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Functional equation and inequality"

1

Yang, Bicheng, and Themistocles M. Rassias. "A Relation to Hilbert’s Integral Inequality and a Basic Hilbert-Type Inequality." In Functional Equations in Mathematical Analysis. Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4614-0055-4_47.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Schwerdtfeger, Hans. "Remark On an Inequality for Monotonic Functions." In Functional Equations and Inequalities. Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-11004-7_15.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Choczewski, Bogdan. "Note on a Functional—Differential Inequality." In Functional Equations — Results and Advances. Springer US, 2002. http://dx.doi.org/10.1007/978-1-4757-5288-5_3.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Yang, Bicheng. "On a Hilbert-Type Integral Inequality." In Functional Equations in Mathematical Analysis. Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4614-0055-4_45.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Yang, Bicheng. "An Extension of Hardy–Hilbert’s Inequality." In Functional Equations in Mathematical Analysis. Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4614-0055-4_46.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Becker, L. C., T. A. Burton, and S. Zhang. "Functional Differential Equations and Jensen’s Inequality." In Dynamics of Infinite Dimensional Systems. Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/978-3-642-86458-2_4.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Tamilvanan, S., E. Thandapani, and J. M. Rassias. "Hyers–Ulam Stability of First Order Differential Equation via Integral Inequality." In Frontiers in Functional Equations and Analytic Inequalities. Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-28950-8_9.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Czerni, Marek. "Solutions of a Functional Inequality in a Special Class of Functions." In Functional Equations and Inequalities. Springer Netherlands, 2000. http://dx.doi.org/10.1007/978-94-011-4341-7_4.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Mićić, Jadranka, and Marjan Praljak. "Recent Research on Levinson’s Inequality." In Frontiers in Functional Equations and Analytic Inequalities. Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-28950-8_32.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Czerni, Marek. "On Dependence of Lipschitzian Solutions of Nonlinear Functional Inequality on an Arbitrary Function." In Functional Equations and Inequalities. Springer Netherlands, 2000. http://dx.doi.org/10.1007/978-94-011-4341-7_5.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Functional equation and inequality"

1

Mansimov, Kamil. "Necessary optimality conditions of the first and second orders in the problem of control of processes described by difference analogy of volterra equation under equality and inequality type functional constraints." In 2012 IV International Conference "Problems of Cybernetics and Informatics" (PCI). IEEE, 2012. http://dx.doi.org/10.1109/icpci.2012.6486436.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Nakhaie-Jazar, Gholamreza, A. H. Naghshineh-Poor, and K. Ravanbakhsh. "Energy Optimal Control Algorithm Based on Central Difference Approximation of Equation of Motion With Application to Robot Control." In ASME 1992 International Computers in Engineering Conference and Exposition. American Society of Mechanical Engineers, 1992. http://dx.doi.org/10.1115/cie1992-0131.

Full text
Abstract:
Abstract Optimal control of robotic manipulator has a complex nature. Many different control and optimal control algorithms have been developed. However, these algorithms are either based on simplified equation of motion or are tedious to implement to set up. In this work the equations of motion are approximated by central difference technic and Taylor series expansion, while path of motion is divided in finite segments. The motion is assumed to have zero velocity at beginning and at the end of the motion, without loss of generality. The whole time and path of motion is arbitrary, but fixed, a
APA, Harvard, Vancouver, ISO, and other styles
3

WOJTECZEK, KATARZYNA. "CLASSES OF FUNCTIONS FULFILLING SECOND ORDER HARDY TYPE INTEGRAL INEQUALITIES ON THE EXAMPLE OF 'STANDARD' HARDY INEQUALITY." In Proceedings of the International Conference on Differential Equations. WORLD SCIENTIFIC, 2005. http://dx.doi.org/10.1142/9789812702067_0206.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Banik, A. K., and T. K. Datta. "Stochastic Response and Stability Analysis of Two-Point Mooring System." In ASME 2011 30th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2011. http://dx.doi.org/10.1115/omae2011-49714.

Full text
Abstract:
The stochastic response and stability of a two-point mooring system are investigated for random sea state represented by the P-M sea spectrum. The two point mooring system is modeled as a SDOF system having only stiffness nonlinearity; drag nonlinearity is represented by an equivalent linear damping. Since no parametric excitation exists and only the linear damping is assumed to be present in the system, only a local stability analysis is sufficient for the system. This is performed using a perturbation technique and the Infante’s method. The analysis requires the mean square response of the s
APA, Harvard, Vancouver, ISO, and other styles
5

Berezhnoi, Eugenii I., Victoria V. Kocherova, and Alexei A. Perfilyev. "Notes for Trudinger–Moser inequality." In INTERNATIONAL CONFERENCE “FUNCTIONAL ANALYSIS IN INTERDISCIPLINARY APPLICATIONS” (FAIA2017). Author(s), 2017. http://dx.doi.org/10.1063/1.5000608.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Sadybekov, Makhmud, and Aidyn Kassymov. "An isoperimetric inequality for heat potential and heat equation." In INTERNATIONAL CONFERENCE ON ANALYSIS AND APPLIED MATHEMATICS (ICAAM 2016). Author(s), 2016. http://dx.doi.org/10.1063/1.4959643.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Zhou Zhongcheng. "Lyapunov inequality for linear elliptic equation, an optimal control approach." In 2008 Chinese Control Conference (CCC). IEEE, 2008. http://dx.doi.org/10.1109/chicc.2008.4605828.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Luo, D., Y. Liu, C. Wang, and X. Tan. "An Observability Inequality On A Kind of Linear Parabolic Equation." In 2017 International Seminar on Artificial Intelligence, Networking and Information Technology (ANIT 2017). Atlantis Press, 2018. http://dx.doi.org/10.2991/anit-17.2018.25.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Kalybay, Aigerim, and Danagul Karatayeva. "An extended discrete weighted Hardy inequality in the difference form." In INTERNATIONAL CONFERENCE “FUNCTIONAL ANALYSIS IN INTERDISCIPLINARY APPLICATIONS” (FAIA2017). Author(s), 2017. http://dx.doi.org/10.1063/1.5000611.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Tarulli, Mirko, and George Venkov. "A functional inequality associated to a Gagliardo-Nirenberg type quotient." In PROCEEDINGS OF THE 43RD INTERNATIONAL CONFERENCE APPLICATIONS OF MATHEMATICS IN ENGINEERING AND ECONOMICS: (AMEE’17). Author(s), 2017. http://dx.doi.org/10.1063/1.5013981.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Reports on the topic "Functional equation and inequality"

1

Lau, K. S., and H. M. Gu. A Note on an Integrated Cauchy Functional Equation. Defense Technical Information Center, 1985. http://dx.doi.org/10.21236/ada160339.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Mitoma, Itaru. Weak Solution of the Langevin Equation on a Generalized Functional Space,. Defense Technical Information Center, 1988. http://dx.doi.org/10.21236/ada194290.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Root, Seth, John H. Carpenter, Kyle Robert Cochrane, and Thomas Kjell Rene Mattsson. Equation of state of CO2 : experiments on Z, density functional theory (DFT) simulations, and tabular models. Office of Scientific and Technical Information (OSTI), 2012. http://dx.doi.org/10.2172/1055894.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Carpenter, John H., Seth Root, Kyle Robert Cochrane, Dawn G. Flicker, and Thomas Kjell Rene Mattsson. Equation of state of argon : experiments on Z, density functional theory (DFT) simulations, and wide-range model. Office of Scientific and Technical Information (OSTI), 2012. http://dx.doi.org/10.2172/1055655.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Williams, Todd O. FUNCTIONAL ANALYSIS OF THE LIPPMANN-SCHWINGER EQUATION FOR THE DETERMINATION OF THE POINTWISE MECHANICAL AND TRANSFORMATION FIELD CONCENTRATION TENSORS IN HETEROGENEOUS MATERIALS. Office of Scientific and Technical Information (OSTI), 2013. http://dx.doi.org/10.2172/1063253.

Full text
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!