@misc{indiciaea575cedb27ba,
  title = {Harmonic entanglement with second-order nonlinearity.},
  author = {Nicolai B Grosse and Warwick P Bowen and Kirk McKenzie and Ping Koy Lam},
  year = {2006},
  doi = {10.1103/physrevlett.96.063601},
  url = {https://pubmed.ncbi.nlm.nih.gov/16605992/},
  note = {Source identifier: 16605992}
}