@Misc{ 
  ManMor14,
  author = { Manno, Gianni and Moreno, Giovanni },
  title = { Meta-Symplectic Geometry of $3^{\rm rd}$ Order Monge-Ampère Equations
  and their Characteristics },
  journal = {  },
  year = { 2014 },
  pages = {  },
  URL = { https://gecogedi.dimai.unifi.it/paper/386/ },
  note = { cvgmt preprint}
}