Various early papers on electromagnetics from the original researchers
Title: Electromagnetic Theory, Volume I Author: Oliver Heaviside Pub date: 1889 Electromagnetic Theory, Vol 1 by Oliver Heaviside on archive.org Title: Electromagnetic Theory, Volume II Author: Oliver Heaviside Pub date: 1889 Electromagnetic Theory, Vol 2 by Oliver Heaviside on archive.org
- - - - - - - - - - Title: Electric Waves Author: Dr. Heinrich Hertz, D. E. Jones (translator) Pub date: 1893 "Electric Waves" by H. Hertz on archive.org
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Title: Direction and Position Finding by Wireless Author: Ronald Keen Pub date: 1922 Radio Direction Finding by Keen on archive.org
Updated edition:
Title: Wireless Direction Finding and Directional Reception Author: Ronald Keen Pub date: 1927 Wireless Direction Finding on ebook.lib.hku.hk by R. Keen
the truth about loops 