Аннотация:The systems
dx/dt=f(t,x)](1)
and
dx/dt=f(t,x)+μR(t,x)(2)
are considered in the domain G=I×B H ,I=[0,∞),B H ={x∈ℝ n :∥x∥<H},μ≪1. It is supposed that systems (1),(2) have the zero solutions. The zero solution of system (1) is assumed to be nonasymptotically stable. Conditions on R are obtained such that the zero solution of system (2) is stable, asymptotically stable, or unstable, respectively.