@misc{indiciaecc63eda1eb6f,
  title = {Variational principles for nonsmooth metrics.},
  author = {G Hayward and J Louko},
  year = {1990},
  doi = {10.1103/physrevd.42.4032},
  url = {https://pubmed.ncbi.nlm.nih.gov/10012814/},
  note = {Source identifier: 10012814}
}