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GB121474A
|
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Improvements in or relating to Electric Selectors for Telephone Systems.
|
|
US1256322A
|
|
Semi-automatic telephone-exchange.
|
|
GB100113A
|
|
Improvements in or relating to Semi-automatic Telephone Exchange Systems.
|
|
US1250885A
|
|
Automatic telephone-exchange system.
|
|
US1186908A
|
|
Automatic selector-switch.
|
|
GB191416234A
|
|
Improvements in Automatic Selector Switches for Telephone Exchange Systems.
|
|
US1239011A
|
|
Automatic telephone-exchange system.
|
|
GB191105812A
|
|
Improvements in Channels or Conduit Sections for Underground Cables and Method of Manufacturing same.
|
|
GB191105813A
|
|
Improvements in Apparatus for Manufacturing Conduits for Underground Cables.
|
|
US697845A
|
|
Conduit for electric or like cables.
|
|
GB190105227A
|
|
Improvements in or relating to the Arrangement of Electrical Cables or Groups of Conductors.
|
|
GB190105134A
|
|
Improvements in Conduits for Electric Cables and the like.
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