We have recently been alerted to the fact that an article published in Minerva had a double in the journal Scientometrics where it had been published by the same author just a few weeks before. A check of text overlap produced a disturbing result: 29% text identity, two tables and four figures exhibited the same numbers even though the format differed slightly. It is a case of ‘self-plagiarism’. Many of us if not all have done this, myself included, with one important exception: text which has already appeared in another context must be cited so that editors and reviewers are aware of the multiple use of text. No one can expect them to find such cases on their own. Unless someone sees these duplications by accident, they go unnoticed and inflate the communication process. But scholars, editors and reviewers need to know because journal space is scarce and so is the time researchers spend looking for results relevant to their own work, not to mention the time reviewers are asked to spend on providing constructive criticism to authors. Unnecessary and hidden multiplication of text and results abuses both. To protect these scarce resources, covert duplication has become a matter of concern for journals and research councils. While so far little is known about duplicate publication in social sciences and the humanities, other disciplines have already reacted. von Elm et al. (2004) proposed a decision tree for identification of duplicate publications, based on a study in anesthesia and analgesia (the current case could fit for pattern 1 A of this decision tree): ‘‘Duplicate publication is the publication of an article that overlaps substantially with an article published elsewhere. This practice may be acceptable in particular situations. However, authors must acknowledge the main article overtly by using a cross-reference. Covert duplicate publication has been widely disapproved. This practice is wasteful