Zeng, Introduction to Wireless and Mobile Systems (2nd Edition, published by Thomson, April 2005) ISBN 978-0-534-49303-5 ↑ J.K. and K. Ross, Computer Networking (2nd Ed, Addison Wesley, 2003) ISBN 978-0-321-17644-8 ↑ The schematics are illustrated in U.S. Patent 613,809 and describes "rotating coherers". ↑ "High-tech bugging techniques, and a costly fix".