@Article{ 
  muc06a,
  author = { Mucci, Domenico },
  title = { ${BV}$-maps with values into ${S^1}$: graphs, minimal connections and optimal lifting },
  journal = { Forum Math. },
  year = { 2008 },
  volume = { 20 },
  number = { 5 },
  pages = { 859-880 },
  URL = { http://cvgmt.sns.it/paper/393/ },
  note = { cvgmt preprint}
}