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 # Extract Bibliographic Info From Alma
 
 [Jupyter Notebook](Extract_Bibliographic_Info_From_Alma.ipynb) for extracting bibliographic information
-for a given list of unique identifiers.
+for a given list of unique identifiers. In the default version this Notebook fetches
+the records by Alma's internal unique ID, the MMS-ID. This is because this ID is
+available for any bibliographic Alma record.
+
+Some information is fetched from the parent record. This relation is queried by an
+ID that is only used within the [Austrian Library Network](https://www.obvsg.at/),
+the AC-number. The Notebook supplies some hints as on how to adapt the Notebook
+for differing hierarchical linking.
 
 ## Setup