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Application filed by Johan Nicolai UlrichsenfiledCriticalJohan Nicolai Ulrichsen
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Publication of DK64554CpublicationCriticalpatent/DK64554C/da
Perfeccionamientos introducidos en los aparatos portátiles de señalamiento óptico y para señales de reconocimiento, particularmente entre naves, entre aviones o entre aviones y naves y estaciones terrestres