@misc{indiciaeb6a3a69fcfe0,
  title = {The elements of electrical engineering; a text book for technical schools and colleges. Vol. II. Alternating currents — Illustration, Page 289},
  year = {1908},
  url = {https://www.biodiversitylibrary.org/page/17500633},
  note = {Source identifier: page-17500633}
}