%0 Journal Article %A PăUN, Gheorghe %T Some consequences of a result of Ehrenfeucht and Rozenberg %J RAIRO. Informatique théorique %D 1980 %P 119-122 %V 14 %N 1 %I EDP-Sciences %U http://www.numdam.org/item/ITA_1980__14_1_119_0/ %G en %F ITA_1980__14_1_119_0