Review articles


Methods for estimating the number of limit cycles of autonomous systems L. A. Cherkas

779 

Ordinary Differential Equations


Geometric classification of a quadratic differential system N. I. Vulpe, K. S. Sibirskii

803 

A construction of the fundamental matrix of solutions of a certain system of differential equations, and a study of its behavior P. B. Golokvoschyus

815 

Characteristic vectors of the solutions of linear homogeneous Pfaffian systems È. I. Grudo

826 

Further development of the theorem of N. G. Četaev on the instability of motion B. P. Demidovich, Yu. V. Malyshev

841 

The minimal exponent of a twodimensional linear differential system N. A. Izobov

848 

Integrability of Abel equations of general form by means of functions that are solutions of second order linear equations N. A. Lukashevich, A. A. Samodurov

859 

Remarks on stationary integrals, and stationary transformations of nonautonomous differential systems V. I. Mironenko

864 

Construction of the equations of programmed motions R. G. Mukharlyamov

869 

Cycles in phase portraits of Morse–Smale systems S. Yu. Pilyugin

874 

Uniformly bounded solutions of linear systems of differential equations V. A. Pliss

883 

Smooth equivalence of systems of differential equations on the plane in the case of a structurally unstable focus S. P. Tokarev

892 

Asymptotically Poisson stable motions of dynamical systems, and their comparability with regard to the recurrence property in the limit B. A. Shcherbakov, D. N. Cheban

898 

Partial Differential Equations


The problem of the excitation of an arbitrary spheroid by a dipole emitter E. A. Ivanov

907 

Solution of a mixed problem for a second order parabolic equation that contains a time derivative in the boundary condition M. L. Rasulov

920 

A boundary value problem for an equation of mixed type of the second kind with displacement M. M. Smirnov

931 

Short Communications


A system with one zero root of the characteristic equation A. F. Andreev, I. V. Pehenko

944 

A certain type of perturbed Bessel equation, and a particular solution of it M. V. Butrov

947 

A method of finding periodic solutions of autonomous systems of differential equations A. E. Gel'man

949 

Topological equivalence of nonautonomous equations N. N. Ladis

951 

A property of matrix exponentials G. N. Petrovskiĭ

954 

Asymptotic stability of the solutions of a certain linear system V. G. Skatetsky

956 

Tests for the instability of a set with respect to a nonautonomous differential system A. A. Shestakov

958 

People of Soviet science


Nikolaǐ Pavlovič Erugin (on the occasion of his seventieth birthday)

961 