%0 Journal Article
%A Yu. I. Romanov
%T Comparison of the strength of certain $\Delta\Sigma$-operations in connection with the generalization of certain multiple separability theorems.
%J Izvestiâ vysših učebnyh zavedenij. Matematika
%D 1968
%P 80-85
%N 3
%I mathdoc
%U http://geodesic.mathdoc.fr/item/IVM_1968_3_a10/
%G ru
%F IVM_1968_3_a10