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A detailed description of all PI formats can be found at httphttps://publicpublicwiki.deltares.nl/display/FEWSDOC/The+Delft-Fews+Published+interface+%28PI%29Interface. The latest versions of the schema files are always available at the Deltares website at: http://fews.wldelft.nl/schemas/version1.0/pi-schemas/pi_timeseries.xsd
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Please consult the full documentation (httphttps://publicpublicwiki.deltares.nl/display/FEWSDOC/The+Delft-Fews+Published+interface+%28PI%29Interface) and the xsd schema for more details.
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