%0 Journal Article %A Christopher Frei %T Sums of units in function fields II: The extension problem %J Acta Arithmetica %D 2011 %P 361-369 %V 149 %N 4 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/aa149-4-5/ %R 10.4064/aa149-4-5 %G en %F 10_4064_aa149_4_5