%0 Journal Article %A Blanchet-Sadri, F. %T On dot-depth two %J RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications %D 1990 %P 521-529 %V 24 %N 6 %I EDP-Sciences %U http://www.numdam.org/item/ITA_1990__24_6_521_0/ %G en %F ITA_1990__24_6_521_0