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README.md

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 This dataset contains 500 invoice documents annotated and processed to be ready for Donut ML model fine-tuning.
 
-Annotation and data preparation task was done by Katana ML team. Original invoice documents are taken from Samples of electronic invoices
+Annotation and data preparation task was done by [Katana ML](https://www.katanaml.io) team.
 
-Sparrow - open-source data extraction solution
+[Sparrow](https://github.com/katanaml/sparrow/tree/main) - open-source data extraction solution.
+
+Raw dataset [info](https://data.mendeley.com/datasets/tnj49gpmtz):
+
+Kozłowski, Marek; Weichbroth, Paweł (2021), “Samples of electronic invoices”, Mendeley Data, V2, doi: 10.17632/tnj49gpmtz.2