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 ### ABAP
 
+* [Einstieg in ABAP](http://openbook.rheinwerk-verlag.de/einstieg_in_abap/) - Karl-Heinz Kühnhauser, Thorsten Franz
 * [SAP Code Style Guides - Clean ABAP](https://github.com/SAP/styleguides/blob/master/clean-abap/CleanABAP_de.md)