Hi,
I recently made the same question to moz support, here is my question and the reply:
QUESTION:
I am having a problem with a duplicated content error
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Crawl Issues Report - Duplicate Page Content for Bajalibros Argentina (www.bajalibros.com/AR)
Generated at Wed Jul 27 15:22:27 +00:00 2016
URL
https://www.bajalibros.com/AR/Samanta-Schweblin-Autor-426833
https://www.bajalibros.com/AR/Catherine-Clement-Autor-184525
THE REPLY
Hi there! I think this has to do with how our tools determine what is duplicate content. Our tool has a 90% tolerance for duplicate content, which means it will flag any content that has 90% of the same code between pages. This includes all the source code on the page and not just the viewable text, so often it's a matter of finding the best answer for the duplicate pages in question.
For instance, often with ecommerce sites, product pages will come up with duplicate content between two colors of the same item, and in that case it's good to use the canonical tag. If there are two versions of the site that exist - for instance, example.com/subfolder andwww.example.com/subfolder - you can put in 301 redirects to the correct page: https://moz.com/learn/seo/redirection. If it's just two pages on different subjects but thin content, filling out that content with an extra paragraph or two can help. 
There are more in-depth explanations of common answers to duplicate content on this page, if you're curious!: https://moz.com/learn/seo/duplicate-content I hope this helps! Let me know if you have any other questions or if there's anything that needs clarifying!
Hope this applies to you too
Best
