@Article{ 
  mostil00,
  author = { Mosconi, Sun-ra J. N. and Tilli, Paolo },
  title = { Variational problems with several volume constraints on the  level sets },
  journal = { Calculus of Variations },
  year = { 2001 },
  pages = {  },
  URL = { http://cvgmt.sns.it/paper/284/ },
  note = { cvgmt preprint}
}