https://digilab.ptb.de/dkd/refType/vocab/ Metrology Database German Calibration Service (DKD) metrology, reference types, digital calibration certificate, certificate of conformity German Calibration Service (DKD) 2023-06-19 en-US 2024-06-05 10:18:35 ruleList 2024-06-05 10:18:35https://digilab.ptb.de/dkd/refType/vocab/skos/4https://digilab.ptb.de/dkd/refType/vocab/skos/185https://digilab.ptb.de/dkd/refType/vocab/skos/184https://digilab.ptb.de/dkd/refType/vocab/skos/311https://digilab.ptb.de/dkd/refType/vocab/skos/312https://digilab.ptb.de/dkd/refType/vocab/skos/191https://digilab.ptb.de/dkd/refType/vocab/skos/188https://digilab.ptb.de/dkd/refType/vocab/skos/348https://digilab.ptb.de/dkd/refType/vocab/skos/186