Here’s a list of papers, books and the like that have informed the pages about the phenomenon of Sporadic E.
Bacon, J (2021) Sporadic-E – where we are now? in RadComm Plus, Vol.6 No.1 at https://rsgb.org/main/blog/front-page-news/2021/05/19/radcom-plus-vol-6-no-1/ accessed on 30th November 2022.
Dzekevich, J (2017) Upper-level Lows and 6-metre Sporadic E, in QST December 2017, Volume 101, Number 12.
Geomagnetic kp and ap Indices: pages relating the various indices, at https://www.ngdc.noaa.gov/stp/GEOMAG/kp_ap.html accessed on 26th October 2021.