%0 Journal Article %A Qi'an Guan %A Xiangyu Zhou %T A solution of an $L^{2}$ extension problem with an optimal estimate and applications %J Annals of mathematics %D 2015 %P 1139-1208 %V 181 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4007/annals.2015.181.3.6/ %R 10.4007/annals.2015.181.3.6 %G en %F 10_4007_annals_2015_181_3_6