References
- R. Adams, J. Fournier, Sobolev Spaces(second ed.), Pure Appl. Math., 140, Academic Press, New York London, 2003.
- L. Barbu, G. Moroşanu, Eigenvalues of the negative (p, q)−Laplacian under a Steklov-like boundary condition, Complex Var. Elliptic, 644(2019), 685700.
- L. Barbu, G. Moroşanu, Full description of the eigenvalue set of the (p, q)-Laplacian with a Steklov-like boundary condition, J. Differential Equations, 290(2021), 1–16.
- L. Barbu, G. Moroşanu, On a Steklov eigenvalue problem associated with the (p, q)−Laplacian, Carpathian J. Math., 37(2021), 161–171.
- L. Barbu, G. Moroşanu, Full description of the spectrum of a Steklov-like eigenvalue problem involving the (p, q)−Laplacian, Ann. Acad. Rom. Sci, Ser. Math. Appl. (in press).
- L. Barbu, G. Moroşanu, On the eigenvalue set of the (p, q)−Laplacian with a Neumann-Steklov boundary condition, Differential Integral Equations. (in press).
- V. Benci, D. Fortunato, L. Pisani, Solitons like solutions of a Lorentz invariant equation in dimension 3, Rev. Math. Phys., 10(1998), 315344.
- V. Bobkov, M. Tanaka, On the Fredholm-type theorems and sign properties of solutions for (p, q)− Laplace equations with two parameters, Ann. Mat. Pura Appl., 198(2019), 16511673.
- D. Bonheure, F. Colasuonno, J. Fldes, On the Born-Infeld equation for electrostatic fields with a superposition of point charges, Ann. Mat. Pura Appl., 198(3) (2019), 749–772.
- H. Brézis, Functional Analysis, Sobolev Spaces and Partial Differential Equations, Springer, 2011.
- E. Casas, L.A. Fernández, A Green’s formula for quasilinear elliptic operators, J. Math. Anal. Appl., 142(1989), 62–73.
- L. Cherfils, Y. Il’yasov, On the stationary solutions of generalized reaction diffusion equations with p&q−Laplacian, Commun. Pure Appl. Anal., 4(2005), 9–22.
- Z. Denkowski, S. Migórski, N.S. Papageorgiou, An Introduction to Nonlinear Analysis: Theory, Springer, New York, 2003.
- G.H. Derrick, Comments on nonlinear wave equations as models for elementary particles, J. Math. Phys., 5(1964), 1252–1254.
- L.F.O. Faria, O.H. Miyagaki, D. Motreanu, Comparison and positive solutions for problems with (p, q)−Laplacian and convection term, Proc. Edinb. Math. Soc., 57 (2) (2014), 687–698.
- L. Gasiński, N.S. Papageorgiou, Exercises in Analysis. Part 2: Nonlinear Analysis, Springer International Publishing, Switzerland, 2016.
- T. Gyulov, G. Moroşanu, Eigenvalues of −(Δp + Δq) under a Robin-like boundary condition, Ann. Acad. Rom. Sci. Ser. Math. Appl., 8(2016), 114–131.
- D. Mugnai, N.S. Papageorgiou, Resonant nonlinear Neumann problems with indefinite weight, Ann. Sc. Norm. Super. Pisa, Cl. Sci., (5)XI(2012), 729788.
- N.S. Papageorgiou, C. Vetro, F. Vetro, Continuous spectrum for a two phase eigenvalue problem with an indefinite and unbounded potential, J. Differential Equations, 268(2020), 41024118.
- M. Struwe, Variational Methods: Applications to Nonlinear Partial Differential Equations and Hamiltonian Systems, Springer, 1996.
- V.V. Zhikov, Averaging of functionals of the calculus of variations and elasticity theory, Izv. Akad. Nauk SSSR Ser. Mat., 50(1986), 675710; English translation in Math. USSR-Izv., 29(1987), 3366.