Radio countermeasures

"Manuscript and illustrations ... prepared for publication by the Summary Reports Group of the Columbia University Division of War Research under contract OEMsr-1131."
Half-title: Summary technical report of the National Defense Research Committee.
Includes index.
The subject indexes of all Summary Technical Report volumes are combined in a master index printed in a separate volume.
LC Science, Business & Technology copy no. 93.
In a set of declassified documents held as a collection by the Library of Congress.
Originally: Secret.
Also available in digital form.