%0 Book %A Auscher, Pascal %A Tchamitchian, Philippe %T Square root problem for divergence operators and related topics %S Astérisque %D 1998 %N 249 %I Société mathématique de France %U http://www.numdam.org/item/AST_1998__249__R1_0/ %G en %F AST_1998__249__R1_0