@misc{indiciae21bc6ff8fe12,
  title = {Negretti \& Zambra's encyclopædic illustrated and descriptive reference catalogue of optical, mathematical, physical, photographic and standard meteorological instruments, manufactured and sold by them — Illustration, Page 167},
  year = {1887},
  url = {https://www.biodiversitylibrary.org/page/16784005},
  note = {Source identifier: page-16784005}
}