1. American Journal Experts (www.aje.com) 
2. BioMed Proofreading LLC (www.biomedproofreading.com/index.htm) 
3. Editage (www.editage.com) 
4. International Science Editing Ltd. (www.internationalscienceediting.com) 
5. ScienceDocs Inc.(www.sciencedocs.com) 
6. SciTechEdit International (www.scitechedit.com) 
7. Stallard Scientific Editing (www.stallardediting.com) 
8. Textcheck (www.textcheck.com) 
9. Write Science Right (www.writescienceright.com/index.html)

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1. Endnote (www.endnote.com) 
2. Mendeley (www.mendeley.com) 
3. Zotero (www.zotero.org) 
4. JabRef (jabref.sourceforge.net) 
5. Bibus(bibus-biblio.sourceforge.net) 
6. Papers(www.papersapp.com) 
7. Google Scholar(scholar.google.com) 

 

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1. CrossRef (www.crossref.org) 
2. CrossCheck (www.crossref.org) 
3. iThenticate (www.ithenticate.com) 
4. CrossMark (www.internationalscienceediting.com) 
5. PaperRater(www.paperrater.com) 
6. PlagTracker (www.plagtracker.com) 
7. Plgiarism Detector (plagiarism-detector.com) 

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1. GetTextbooks (www.gettextbooks.com) 
2. The International ISBN Agency (www.isbn-international.org) 
3. ISBNdb (isbndb.com) 
4. ISBN Search (isbnsearch.org) 
5. SAN Search (https://www.isbn.org/san_lookup) 

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