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Turnitin - Turnitin is preferred by educational institutions around the world for preventing plagiarism. Instructors at all levels of education can request that students use the service to submit papers, and Turnitin checks those papers for plagiarism.
Plagramme - Our plagiarism checker recognizes paraphrased plagiarism, checks your paper against more that 14 trillion documents and lets you to edit your paper online.
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PlagiarismSearch - PlagiarismSearch is online service that detects plagiarized content.
Copyscape - Copyscape is a free plagiarism checker.