Relaciones entre ansiedad social y rasgos, estilos y trastornos de la ... by Caballo, Vicente E.; Salazar, Isabel C.; Irurtia, Maria Jesus; Benito Arias; Guillen, Jose Luis / Behavioral Psychology/Psicologia Conductual.
Dictaphone was prominent in the provision of multi-channel recorders, used extensively in the emergency services to record emergency telephone calls (to numbers such as 911, 999, 112) and subsequent conversations.
Listening Devices that transmit Audio Surveillance over long distance while drawing very low power output are known as Lithium Transmitters. These listening devices are very small and can be placed in hard to view areas.