@misc{1161716,
  author = {M T Duffy and P J Zanzucchi and W E Ham and J F Corboy and GW Cullen},
  title = {Method to determine the quality of sapphire:},
  year = {1980},
  month = {1980-01-01 05:01:00},
  publisher = {, National Institute of Standards and Technology, Gaithersburg, MD},
  doi = {https://doi.org/10.6028/NBS.SP.400-62},
  language = {en},
}