GB256879A
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Improvements in or relating to arc lamps
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GB251129A
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Improvements in electric polyphase current arc lamps
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GB256529A
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Improvements in electric arc lamps with parallel carbons
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GB252495A
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Improvements in or relating to electric arc lamps
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GB246073A
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Improvements in or relating to electric arc lamps
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DE419202C
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Lighting apparatus for photographic, stage lighting and similar purposes
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GB206442A
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Improvements in medical apparatus for ultraviolet ray treatment
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GB191616A
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Improvements in light-radiators for medical purposes
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