The first description and illustration of the duck-billed platypus appeared in the scientific literature in 1799. Since its international debut, the platypus has fascinated the scientific community. The past 200 years of scholarly literature is peppered with journal articles containing taxonomic revisions and details of the bizarre biology and behaviour of this paradoxical species. Yet, despite the fact that much of this historic literature is now accessible online, it is almost impossible to find. This is because, unlike contemporary scientific publications, much of the digitised historical literature lacks article-level citation data and digital object identifiers (DOIs).<br> This paper will detail the work the Biodiversity Heritage Library (BHL) is undertaking to bring the world’s historic literature into the modern linked network of scholarly research. It will present three case studies – three “lost” platypus articles from three very different publications – to demonstrate how the retrospective registration of DOIs is critical to making legacy literature discoverable, citable and trackable. <br> This paper will also discuss the responsibility and accountability that comes with assigning DOIs, including best practice for out-of-copyright and orphaned content, and the issues that arise when the definitive (DOI’d) versions of public domain journal articles are locked behind paywalls.
