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There are four types of identifier that can be used in this context:
1. an HTTP URI that references a linked open data resource external to the data submitted to Europeana
(A dereferenceable Uniform Resource Identifier uses HTTP to obtain a copy or representation of the resource it identifies, see https://en.wikipedia.org/wiki/Linked_data )
2. an HTTP URI that references another resource inside the same metadata description submitted to Europeana
3. a local URI that is not dereferenceable but that refers to another resource inside the same metadata description (e.g. an identifier internal to the provider infrastructure
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)
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4. an identifier that is not dereferenceable but that refers to another resource inside the same metadata description (any string used to identify a resource, such as an inventory number)
Language aspects of the data
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