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README.md

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 # paperetl: ETL processes for medical and scientific papers
 
+[![Version](https://img.shields.io/github/release/neuml/paperetl.svg?style=flat&color=success)](https://github.com/neuml/paperetl/releases)
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 paperetl is an ETL library for processing medical and scientific papers. It supports the following sources:
 
 - [CORD-19](https://www.semanticscholar.org/cord19)