@misc{indiciae29715a7f75db,
  title = {Metro manual, a hand book for engineers; containing technical information regarding the construction, adjustment and use of transits, tachymeters, theodolites, alidades levels, etc — Illustration, Page 21},
  year = {1915},
  url = {https://www.biodiversitylibrary.org/page/17671551},
  note = {Source identifier: page-17671551}
}