%0 Journal Article
%A Cintioli, Patrizio
%A Silvestri, Riccardo
%T The helping hierarchy
%J RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications
%D 2001
%P 367-377
%V 35
%N 4
%I EDP-Sciences
%U http://www.numdam.org/item/ITA_2001__35_4_367_0/
%G en
%F ITA_2001__35_4_367_0