%0 Journal Article %A V. N. Orlov %A O. A. Kovalchuk %T Exact boundaries for the analytical approximate solution of~a~class of first-order nonlinear %J Journal of Samara State Technical University, Ser. Physical and Mathematical Sciences %D 2021 %P 381-392 %V 25 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/item/VSGTU_2021_25_2_a8/ %G en %F VSGTU_2021_25_2_a8