%0 Journal Article
%A V. V. Ivlev
%A E. A. Krivoshey
%T Approximation of the Pfaff equations of several variables
%J Matematičeskoe obrazovanie
%D 2021
%P 57-62
%V 100
%N 4
%I mathdoc
%U http://geodesic.mathdoc.fr/item/MO_2021_100_4_a8/
%G ru
%F MO_2021_100_4_a8