# Differential Equations | 2003(39) articles

- Observable Linear Nonstationary Systems of Total Differential Equations
- Qualitative Analysis of the Singular Cauchy Problem for a Differential Equation Unsolved for the Derivative
- A Criterion for the Invariance of Characteristic Exponents of Linear Systems with a Small Parameter Multiplying the Derivative
- Structural Stability of Nonautonomous Systems
- An Estimate of the Number of Limit Cycles via Critical Points of Conditional Extremum
- Unique Solvability of Nonlocal Boundary Value Problems for Systems of Hyperbolic Equations
- Properties of Solutions of Equations Containing Powers of an Unbounded Operator
- The Riemann Function for Higher-Order Hyperbolic Equations and Systems with Dominated Lower-Order Terms
- Ill-Posed Initial-Boundary Value Problems for Higher-Order Linear Hyperbolic Equations with Two Independent Variables
- Higher-Order Approximations of the Averaging Method for Parabolic Initial-Boundary Value Problems with Rapidly Oscillating Coefficients
- Solvability of a Nonlocal Version of the Gellerstedt Problem
- Weakly Degenerate Hyperbolic Equations
- Optimal Control of an Elliptic Equation with a Nonsmooth Nonlinearity
- A Test for the Completeness of the Root Vectors in the Tricomi Problem
- A Class of Asymptotically Equivalent Spatially Homogeneous Discrete Boltzmann Equations
- Solution of Boundary Value Problems for the Fractional Diffusion Equation by the Green Function Method
- Bifurcation of an Invariant Torus from an Equilibrium Under Commensurability Conditions