@inbook{237896,
  author = {Carl Williams},
  title = {The SI and Quantum Metrology},
  year = {2017},
  number = {196},
  month = {2017-12-01},
  publisher = {Proceedings of the International School of Physics “Enrico Fermi” Vol. 196, IOS Press, Amsterdam, -1},
  language = {en},
}