GR1717B
(en )
1928-01-17
PERFECTIONS IN SEMI-AUTOMATIC TELEPHONE SYSTEMS.
GR1866B
(en )
1928-06-08
PERFECTIONS IN AUTO TELEPHONY SYSTEMS.
GR1621B
(en )
1927-09-30
PERFECTIONS IN AUTOMATIC TELEPHONE SYSTEMS.
GR1677B
(en )
1927-12-02
PERFECTIONS IN AUTOMATIC TELEPHONE SYSTEMS.
GR1378B
(en )
1926-12-31
IMPROVEMENTS IN SEMI-AUTOMATIC TELEPHONE SYSTEMS.
GR2251B
(en )
1929-04-08
PERFECTIONS IN TELEPHONE CALL COUNTING SYSTEMS.
ES94764A3
(en )
1925-11-16
Improvements in automated telephone systems.
GR1312B
(en )
1926-12-16
PERFECTIONS IN AUTOMATIC PHONE SYSTEMS.
ES92395A1
(en )
1925-05-16
Improvements in telephone systems.
ES93082A1
(en )
1925-06-16
Improvements in telephone systems.
ES94381A3
(en )
1925-12-16
Improvements in telephone systems.
ES94945A3
(en )
1925-12-16
Improvements in telephone systems.
ES95859A1
(en )
1926-03-01
Improvements in telephone systems.
ES95932A1
(en )
1926-03-01
Improvements in telephone systems.
ES95958A1
(en )
1926-02-16
Improvements in telephone systems.
ES96167A1
(en )
1926-06-01
Improvements in telephone systems.
ES96305A1
(en )
1926-03-16
Improvements in telephone systems.
ES96310A1
(en )
1926-04-16
Improvements in telephone systems.
ES96357A1
(en )
1926-03-16
Improvements in telephone systems.
ES96059A1
(en )
1926-04-16
Improvements in automated telephone systems.
ES94412A1
(en )
1925-11-01
Improvements in automatic telephone systems.
ES93788A1
(en )
1925-07-16
Improvements in automatic telephone systems in general.
GR942B
(en )
1925-06-13
PERFECTIONS IN SEMATOLOGY SYSTEMS.
ES94682A1
(en )
1925-12-16
Improvements in telephone exchange systems.
AT131968B
(en )
1933-02-25
Self-collecting telephone station.