Update README.md

Author: SevKohler

README.md

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 Eos
 ====
 
+Note
+------
+Eos is the result of a research project. To support our research, please cite one of our papers instead of referencing our github in scientific articles. You can find an overview of papers about Eos here. If you are not sure which paper to cite, we recommend this one:
+
+Severin Kohler, Diego Boscá, Florian Kärcher, Birger Haarbrandt, Manuel Prinz, Michael Marschollek, Roland Eils, Eos and OMOCL: Towards a seamless integration of openEHR records into the OMOP Common Data Model, Journal of Biomedical Informatics, Volume 144, 2023 [(Link)](https://doi.org/10.1016/j.jbi.2023.104437)
+
+
+Thanks!
+
 ![connectEHR](https://user-images.githubusercontent.com/5692615/234679600-432ab931-4561-48fe-8521-1bd57955b3bb.svg)
 
 ## Setup