@Article{ 
  CatRon23,
  author = { Catino, Giovanni and Roncoroni, Alberto },
  title = { A closure result for globally hyperbolic spacetimes },
  journal = { Proc. Amer. Math. Soc. },
  year = { 2024 },
  volume = { 152 },
  number = { 12 },
  pages = { 5339-5354 },
  URL = { http://cvgmt.sns.it/paper/5966/ },
  note = { cvgmt preprint}
}