For the researcher, PIDs are also the quickest way to search for a set of specific publications, datasets or software.

Records in research information system Pure are enhanced with persistent identifiers like DOIs or ISBNs. If you need these you can copy them manually from Research Information portal or you can contact your faculty key-user for an Excel file. Preferably amended with direct links to other sources such as Altmetric Explorer, which you can use to provide a quicker access to the source. If persistent identifiers are missing in Pure or in your own records, you can use other bibliographical databases to see if they provide an identifier for your published output.

Another tool to discover the PID of a book (chapter), dataset, or article is Crossref, or Crossref’s free DOI lookup. If Crossref fails to turn up a DOI, go to the main page of that journal on the publisher website, copy the URL for that main page, and paste that URL following “Retrieved from” in place of the DOI as the final element in the citation. For example; Fink, C. K. (2013). The Cultivation of Virtue in Buddhist Ethics. Journal of Buddhist Ethics, 20. Retrieved from

If there is no DOI discoverable for a print book, the location and publisher remain in their usual place at the end of the citation.  For an e-book with no discoverable DOI, the final element in the citation may be a retrieval statement (e.g. ‘Retrieved from’) rather than either a DOI or a location and publisher.

There are more types of PIDs than types of DOIs and ISBNs. We most commonly see two varieties: those for objects (publications, data, software, such as URNs, DOIs, ARKs, Handle) and those for people (researchers, authors, contributors, such as ORCIDs, ISNIs). Many repositories will assign a PID of the former type when an object is deposited. If a platform does not issue DOIs, or has not yet issued a DOI for an object, use their ID’s to point to the places where they are published, such as PubMed IDs, ISBNs, e-ISBNs, Handles, arXiv IDs, ADS IDs, SSRN IDs, RePEC IDs, URNs or the record number.

When citing software make sure to use the DOI that refers to the correct version.