@Article{ 
  butmaiste09,
  author = { Buttazzo, Giuseppe and Mainini, Edoardo and Stepanov, Eugene },
  title = { Stationary configurations for the average distance functional and related problems },
  journal = { Control Cybernet. },
  year = { 2009 },
  volume = { 38 },
  number = { 4A },
  pages = { 1107-1130 },
  URL = { http://cvgmt.sns.it/paper/202/ },
  note = { cvgmt preprint}
}