Know catalog modifications.
This tool will take a batch of record numbers for either bibliographic records or authority records and allow you to delete all those records and any items attached to them in a batch.

First you need to tell the tool if you're deleting bibliographic or authority records. Next you can load a file with biblionumbers or authids or enter a list of those numbers in the box provided. Once you submit the form you will be presented with a summary of the records you are trying to delete.

If a record you want to delete can't be deleted it will be highlighted.
Check the records you want to delete and click the 'Delete selected records' button to finish the process.