@Misc{ 
  CatRon23,
  author = { Catino, Giovanni and Roncoroni, Alberto },
  title = { A closure result for globally hyperbolic spacetimes },
  journal = {  },
  year = { 2023 },
  pages = {  },
  URL = { http://cvgmt.sns.it/paper/5966/ },
  note = { cvgmt preprint}
}