The principles underlying radio communication (1922)
United States. National Bureau of Standards, Ould, Richard Sheldon, 1889-, United States. Army. Signal Corps · Washington, Govt. Print. Off. · leaf 5
The Principles UnderlyingRadio Communication (SECOND EDITION) Radio Communication Pamphlet No. 40Prepared by the Bureau of Standards Revised to May 24, 1921 Signal Corps, U. S. Army
Telegraph, Wireless · Radio
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