@misc{1189761,
  author = {Ernest E Hughes and William D Dorko and John K Taylor},
  title = {System for preparation of known concentrations of methane in air:},
  year = {1973},
  month = {1973-01-01 05:01:00},
  publisher = {, National Institute of Standards and Technology, Gaithersburg, MD},
  doi = {https://doi.org/10.6028/NBS.IR.73-255},
  language = {en},
}