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OGC Catalogue Services 3.0 Specification - HTTP Protocol Binding (OpenSearch) 3.0

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Open Source Geospatial Foundation

pycsw 2.0
OGC Catalogue Services 3.0 Specification - HTTP Protocol Binding (OpenSearch) 3.0 (Certified: 2016-11-30)
Official OGC® Reference Implementation | License | Source Code
  Registered: 2016-08-22

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Scanpoint Geomatics Ltd.

IGiS Enterprise Suite 5.0
OGC Catalogue Services 3.0 Specification - HTTP Protocol Binding (OpenSearch) 3.0 (Certified: 2017-02-03)
  Registered: 2016-04-08