In an incoming call service by which an extension can be directly called when a call comes in from another office, a dedicated terminal for selecting an extension to which the incoming call is connected is installed to enable the user to select it as desired, thereby increasing usage of call incoming...http://www.google.de/patents/US5541992?utm_source=gb-gplus-sharePatent US5541992 - System for connecting an incoming call to a selected one of a number of extensions
