%0 Journal Article
%A V. P. Orevkov
%T Unsolvability in constructive predicate calculus of a class of formulas of type $\daleth\daleth\forall\exists$
%J Doklady Akademii Nauk
%D 1965
%P 581-583
%V 163
%N 3
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DAN_1965_163_3_a10/
%G ru
%F DAN_1965_163_3_a10