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Considering the ethical and professional implications of self plagiarism, it is very useful to check new manuscript against old ones (which are under review and not yet published) to decrease self plagiarism. In a white paper by ithenticate (download from http://www.ithenticate.com/self-plagiarism-free-white-paper), one way to avoid self plagiarism is to significantly paraphrase those text which are need to be used in new article. However, I have difficulties in identifying the similarity percentage of my current work against yet-unpublished works. Online tools (that I know) check the manuscript against published works. I have 3 journal papers, 1 is published, 1 is under review, and 1 is under preparation. Now, I need to check the third one to see the similarity score. Any suggestion?