@misc{indiciaeb20fda10c62a,
  title = {Pressure control of a gas by a calculator-operated mercury piston},
  author = {Tyler B. Coplen},
  year = {2002},
  doi = {10.1021/ac00229a057},
  url = {https://pubs.usgs.gov/publication/70012149},
  note = {Source identifier: 70012149}
}