When should I include a DOI or URL in an APA journal citation?
In an APA journal citation, if a DOI (digital object identifier) is available for an article, always include it.
If an article has no DOI, and you accessed it through a database or in print, just omit the DOI.
If an article has no DOI, and you accessed it through a website other than a database (for example, the journal’s own website), include a URL linking to the article.