@Article{ giamuc05c, author = { Giaquinta, Mariano and Mucci, Domenico }, title = { $W^{1/2}$-maps into $S^1$ and currents }, journal = { Rend. Accad. Naz. Sci. XL Mem. Mat. Appl. (5) }, year = { 2005 }, volume = { 29 }, number = { 1 }, pages = { 183-206 }, URL = { http://cvgmt.sns.it/paper/664/ }, note = { cvgmt preprint} }