@misc{indiciae7d276282b3ce, title = {Methods and standards for environmental measurement : proceedings of the 8th Materials Research Symposium held at the National Bureau of Standards, Gaithersburg, Maryland, September 20-24, 1976 — Illustration, Page 181}, year = {1977}, url = {https://www.biodiversitylibrary.org/page/41747261}, note = {Source identifier: page-41747261} }