A paper (hypothesis) was submitted and sent out for peer review. One of the reviewers pointed out that large parts of the paper had been published, almost word for word, in a previous publication not cited by the authors. We rejected the paper voicing concern about the previous publication of largely similar material. The authors have appealed against our decision to reject the paper and said that they did not agree with our assessment of duplicate publication, arguing that the repetitions are mostly quotations from the literature and in words they amount to around 10 per cent of the paper. We rejected the paper again. Should we have done/do more?
_ The authors had failed to declare any overlap, and this could possibly be a case of plagiarism. _ Two independent reviewers should decide on the degree of overlap. _ The editor should inform the reviewers of the background of the case.
An independent reviewer confirmed that there was substantial overlap with the previous publication (also a hypothesis), so the rejection was upheld. The editors wrote to the authors, issuing a warning about the need to maintain good publication ethics.