%0 Journal Article %A Tadeusz Iwaniec %T Projections onto gradient fields and $L^{p}$-estimates for degenerated elliptic operators %J Studia Mathematica %D 1982 %P 293-312 %V 75 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/sm-75-3-293-312/ %R 10.4064/sm-75-3-293-312 %G en %F 10_4064_sm_75_3_293_312