Lauren Coffey writes: “More than 2 million scholarly articles are not being properly archived, according to a new analysis. A study published in the Journal of Librarianship and Scholarly Communication in January reviewed more than 7 million documents with digital object identifiers (DOIs). The DOIs are unique identifiers given to most—but not all—scholarly articles, acting as a digital fingerprint. Of the 7,438,037 articles, roughly 28 percent, or more than 2 million works, did not appear in the reviewed archives despite having a DOI.”