@Article{ 
  BagFesMar20,
  author = { Bagagiolo, Fabio and Festa, Adriano and Marzufero, Luciano },
  title = { Hybrid control for optimal visiting problems for a single player and for  a crowd },
  journal = { Nonlinear Differential Equations and Applications },
  year = { 2022 },
  doi = { 10.1007/s00030-021-00737-0 },
  volume = { 29 },
  number = { 1 },
  pages = {  },
  URL = { http://cvgmt.sns.it/paper/4961/ },
  note = { cvgmt preprint}
}