@misc{1191661,
  author = {Elmer L Peffer and Mary G Blair},
  title = {Circular of the Bureau of Standards no. 477::testing of hydrometers},
  year = {1949},
  month = {1949-01-01 05:01:00},
  publisher = {, National Institute of Standards and Technology, Gaithersburg, MD},
  doi = {https://doi.org/10.6028/NBS.CIRC.477},
  language = {en},
}