Vol. 61, No. 8, 2025

Differential Equations

Sufficient Hyperbolicity Conditions for Flows

S. D. Glyzin and A. Yu. Kolesov p. 1197 abstract

Singular and Fixed Points of a Mapping Generated by a Multidimensional System of Ordinary Differential Equations with Relay Hysteresis

A. M. Kamachkin, V. V. Yevstafyeva, and D. K. Potapov p. 1217 abstract

On a Class of Periodic \(E \)-Functions

A. Ya. Yanchenko p. 1225 abstract

On a Property of a Biharmonic Function in an Unbounded Domain in \(\mathbb {R}^3\)

Z. R. Ashurova, N. Yu. Juraeva, U. Yu. Juraeva, and F. U. Mallaeva p. 1232 abstract

Criterion for the Solvability of the Cauchy Problem for the Biharmonic Equation in \(\mathbb {R}^3\) and Analytic Continuation of the Solution

O. I. Makhmudov and I. E. Niyozov p. 1243 abstract

Averaging in a Neumann Sieve-Type Domain with “Light” Concentrated Masses. Subcritical Case

T. D. Kalyaev p. 1254 abstract

On Sufficient Conditions for Optimality in the Weight Minimization Problem for a Shell of Revolution at a Given Vibration Frequency

M. H. Arabyan p. 1274 abstract

Stabilization of a Switched Interval System with Commensurate Delays under Slow Switchings

A. V. Il’in, A. S. Fursov, and Yu. M. Mosolova p. 1285 abstract

Observability of Time-Varying Discrete Descriptor Systems

A. A. Shcheglova p. 1296 abstract

Conservative Compact and Monotone Fourth-Order Difference Schemes for One- and Two-Dimensional Quasilinear Equations

P. P. Matus, G. Ph. Gromyko, B. D. Utebaev, and V. T. K. Tuyen p. 1317 abstract

Generalization of the Oblique Derivative Problem for the Helmholtz Equation in a Disk

A. A. Polosin p. 1333 abstract