Q: Can I publish two papers in different languages using the same data and methods, but as a more elaborate version?
We had submitted a paper to a Non-English journal and it was accepted in January. Now I plan to write the same paper in English. Both the papers use the same data and methods. But the new version is an expanded form of the former one. Also, detailed explanation of the method and interpretation of the result is described. Will this be regarded as duplicate submission or self-plagiarism?
Essentially, most journals require you to declare if your manuscript has been published previously and usually discourage publication of the same manuscript in another language. If you do, however, want to publish with additional data, it might be possible. For this, you will first need to obtain permission from the first journal that published your paper. Once this journal authorizes, you will need to provide the permission letter to the next target journal. You will also need to find a target journal which accepts such publications. Once you find a suitable target journal, please mention the previous publication of the manuscript in another language in the cover letter for this journal. Please also clearly highlight the new data that you have added to the English manuscript to emphasize on the novelty of this paper. This might make a case for separate publication of the English manuscript.