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The BRO GLD doesn't have multiple parameters (in the FEWS sense) , most likely only the head parameteronly the heads in reference to NAP (for details see Basisregistratie Ondergrond Catalogus Grondwaterstandonderzoek (geostandaarden.nl)), so the external BRO parameter will always be mapped to the specified internal parameterId. This also means that the timeSeriesSets should only hold 1 parameterId.
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