@Article{ 
  CarTen19,
  author = { Borrelli, William and Carlone, Raffaele and Tentarelli, Lorenzo },
  title = { A note on the Dirac operator with Kirchoff-type vertex conditions on noncompact metric graphs },
  journal = { Springer INdAM Series },
  year = { 2021 },
  doi = { 10.1007/978-3-030-60453-0 },
  volume = { 42 },
  pages = { 81-104 },
  URL = { http://cvgmt.sns.it/paper/4675/ },
  note = { cvgmt preprint}
}