|
GB219604A
|
|
Improvements in sound detecting apparatus
|
|
GB221727A
|
|
Improvements in subaqueous sound receiving apparatus
|
|
GB222425A
|
|
Improvements in or relating to submarine signalling apparatus
|
|
US1582105A
|
|
Submarine signaling apparatus
|
|
US1485539A
|
|
Sound-receiving apparatus
|
|
US1485538A
|
|
Sound-detecting apparatus
|
|
US1461056A
|
|
Signaling apparatus
|
|
CA240775A
|
|
Signalling apparatus
|
|
CA276879A
|
|
Submarine sound mechanism
|
|
CA262475A
|
|
Sound diaphragm
|
|
CA307764A
|
|
Submarine signalling apparatus
|
|
CA238592A
|
|
Sound receiving apparatus
|
|
CA267172A
|
|
Submarine signal
|
|
CA245462A
|
|
Sound detecting apparatus
|
|
CA244828A
|
|
Visual and aural determination of direction and distance of sounds
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