Page Comparison

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Upon creation in MorphoSource, all media have a standard URL and an ARK.  DOIs must be requested by emailing "morphosource@duke.edu". See Protocol for DOI assignmentDOI Persistent Identifiers for Media.

Practices

• Cite a resolvable identifier (i.e., do NOT "only" list the media id)
• When citing a resolveable identifier, do not cite URLs (they tend to be unstable and are not guaranteed to be globally unique)
• Only cite ARKs in special circumstances
• Cite a DOI whenever possible.

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DOIs are best practice because they are resolveable, unique and permanent (see table).  ARKs are secondary because while they are resolvable and unique, they are not permanent. ARKs are widely treated as disposable identifiers.  When "permanent" means in the case of the web pages is that that DOI will be remain associated with the given media webpage whatever happens to its boutique URL or if it becomes managed via other servers, etc.  It also means that if the resource ultimately becomes unavailable (e.g., because a resource is taken down due to an error or privacy concerns, etc.) the page will resolve to a "tombstone" which provides transparency into the fate of the resource (if not access to it). Finally, because DOIs are more permanent, MorphoSource also  requires users to request DOIs be minted.  This gives the MorphoSource team a chance to review the media for basic quality and request edits/revisions before assigning the identifier.  Therefore, while MorphoSource does not guarantee quality for any of its media, generally speaking media with a DOI should be of more reliable quality.  If you need a DOI assigned see Protocol for DOI assignmentDOI Persistent Identifiers for Media