Über die Funktionalgleichung f(x) = ... In den Körpern ... .
Über die Minimallösung der Poincaré-Perronschen Differenzgleichung.
Über die Struktur der rationalen Operatoren in der zweidimensionalen diskreten Operatorenrechnung
Un puente entre una ecuación diferencial ordinaria y un sistema dinámico discreto vía ecuaciones diferenciales con retardo.
Unbounded perturbations of nonlinear second-order difference equations at resonance.
Unboundedness results for systems
We study k th order systems of two rational difference equations In particular we assume non-negative parameters and non-negative initial conditions. We develop several approaches which allow us to prove that unbounded solutions exist for certain initial conditions in a range of the parameters.
Une résolution élémentaire d'un problème de scission de séparatrices
Uniformly continuous solutions of difference equations with continuous time
Uniqueness and multiplicity of solutions for a second-order discrete boundary value problem with a parameter.
Uniqueness implies existence for discrete fourth order Lidstone boundary-value problems.
Upper and lower solutions method for discrete inclusions with nonlinear boundary conditions.