digital object identifier DOI Type of digital Persistent Identifier (PID) issued by the International DOI Foundation. This permanent digital identifier is associated with an object that permits the object to be referenced reliably even if its location and metadata undergo change over time. https://orcid.org/0000-0002-5214-4466 https://orcid.org/0000-0002-7702-4495 https://orcid.org/0000-0003-2687-1982 persistent identifier