New Services in PBX and Centrex Systems
V. Witkus · IRE Transactions on Communications Systems · 1968
A new concept in telephone customer relations provides "service packages" instead of specifying hardware combinations. Three packages provide from 10 to 16 features for PBX customers. Two packages for Centrex service provide 10 and 14 features, respectively. All packages supply operator console positions in place of the traditional switchboard.