Christian Hirt, Sébastien Guillaume, Annemarie Wisbar, Beat Bürki, Harald Sternberg: Monitoring of the refraction coefficient in the lower atmosphere using a controlled set-up of simultaneous reciprocal vertical angle measurements. In: Journal of Geophysical Research. Band116, Nr. D21, 2. November 2010, doi:10.1029/2010JD014067.
JS28 Integration of Techniques and Corrections to Achieve Accurate Engineering - Jean M. Rüger: Refractive Index Formulae for Radio Waves. Auf: fig.net vom 19.–26. April 2002; zuletzt abgerufen am 27. Dezember 2020.