ISO 24619:2011 specifies requirements for the persistent identifier (PID) framework and for using PIDs for referencing and citing documents, files and language resources (e.g digital dictionaries, text corpora, linguistic annotated corpora). A PID is an electronic identification referring to or citing electronic documents, files, resources, resource collections such as books, articles, papers, images etc. ISO 24619:2011 also addresses issues of persistence and granularity of references to resources, first by requiring that persistent references be implemented by using a PID framework and further by imposing requirements on any PID frameworks used for this purpose.

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