Vol. 67, No. 4, 2026

Siberian Mathematical Journal

The Concept of a \( t \)-Basis and an Application to the Fredholmness of a Banach-Valued Boundary Value Problem with Oblique Derivative

B.T.Bilalov, S.R.Sadigova, and Y.Sezer p. 745 abstract

Spectra of Normalized Volumes of Right-Angled Hyperbolic Polyhedra

A.Yu.Vesnin and A.A.Egorov p. 756 abstract

Formulas for Quasi-Interpolation by Integral Quadratic Splines

Yu.S.Volkov, T.Zhanlav, and R.-O.Mijiddorj p. 774 abstract

Object-Oriented Data via Prefix Rewriting. Part II: Effective Analysis of Rewriting

A.E.Gutman p. 785 abstract

The Perron Method in the Dirichlet Problem for the Soft Laplacian on a Stratified Set

N.S.Dairbekov, O.M.Penkin, and D.V.Savasteev p. 793 abstract

The Kegel–Wielandt \( \sigma \)-Problem and \( TI \)-Subgroups of Finite Groups

X.Yi, S.F.Kamornikov, and V.N.Tyutyanov p. 804 abstract

Graphs of Mappings of Engel Groups and a Criterion for Their Intrinsic Lipschitz Property

M.B.Karmanova p. 811 abstract

Degenerate Pseudoparabolic Equations of the Third Order

A.I.Kozhanov and B.V.Zhigzhitzhapov p. 832 abstract

Carpet Lie Rings Not Invariant with Respect to Carpet Subgroups

Ya.N.Nuzhin p. 840 abstract

The Full Range of Convergence Rates of Birkhoff Averages for Ergodic Flows

I.V.Podvigin and V.V.Ryzhikov p. 846 abstract

An Inverse Problem for the Westervelt Equation

V.G.Romanov p. 856 abstract

Boundedness and Unitarity Conditions in Lebesgue Spaces for Integral Operators with Special Legendre Functions in the Kernels

S.M.Sitnik and O.V.Skoromnik p. 864 abstract

Structure and Automorphisms of Some Cyclic Extensions of Free Groups

E.A.Shaporina p. 890 abstract

On Pell Numbers Representable as a Product of Two Generalized Fibonacci Numbers

J.J.Bravo, P.Das, J.L.Herrera, and J.C.Saunders p. 896 abstract

On the Fourth Moments of Exponential Sums Weighted by Dirichlet Characters

S.Cao and T.Wang p. 906 abstract

On the Distribution of \( \alpha p^{3} \) Modulo One over Special Primes

S.I.Dimitrov and M.D.Lazarova p. 922 abstract

Second-Order Monotone Finite-Difference Schemes for Time-Fractional Quasilinear Parabolic Equations

L.M.Hieu p. 933 abstract

Well-Coveredness and Cohen–Macaulayness of Comaximal Ideal Graphs

M.Sivankutty p. 948 abstract

\( (q,m) \)-Dichotomy and Periodic Solutions for Sylvester Matrix Volterra Integro-Dynamic Systems on Time Scales

A.Sreenivasulu, B.V.Appa Rao, and K.A.S.N.V.Prasad p. 955 abstract

Continuous Fields of Orlicz Spaces on Locally Compact Groupoids and Related Results

K.N.Sridharan and N.S.Kumar p. 967 abstract

Order Structure of the Space of Partial Integral Operators

B.B.Tasoev p. 984 abstract