@misc{indiciaee6a14d06dd86,
  title = {Variability of PI calculations.},
  author = {C J Ruissen and J M van Vugt and J de Haan},
  year = {1988},
  doi = {10.1016/0028-2243(88)90125-6},
  url = {https://pubmed.ncbi.nlm.nih.gov/2965039/},
  note = {Source identifier: 2965039}
}