%0 Journal Article %A Dahlberg, Björn E. J. %A Kenig, Carlos E. %A Pipher, Jill %A Verchota, G. C. %T Area integral estimates for higher order elliptic equations and systems %J Annales de l'Institut Fourier %D 1997 %P 1425-1461 %V 47 %N 5 %I Association des Annales de l’institut Fourier %U http://archive.numdam.org/articles/10.5802/aif.1605/ %R 10.5802/aif.1605 %G en %F AIF_1997__47_5_1425_0