Dealing with duplicate references
When new references are added to your library, EndNote does not automatically check for duplication. Duplicate references within your EndNote library are a potential source of confusion and errors. It is recommended that you delete any duplicates.
EndNote identifies a reference as a duplicate if two or more references are assigned the same reference type (e.g. book) and include the same information in the author, year and title fields.
To identify and delete duplicate references:
1. Select Library in the Toolbar.
2. Select Find Duplicates.
3. A pop-up window appears, EndNote compares two references side by side. Any fields within the references that differ from each other will be highlighted blue.
4. Check the highlighted field and decide which reference to keep. Click Keep this record. You can also edit the reference you want to keep with information from the record you will delete.
Please note: Occasionally EndNote's Find Duplicates function does not identify all duplicates. It is recommended that you regularly sort your references by title to look for duplicates missed previously.
Video credited to EndNote Training.
EndNote Training. (2021, August 25). In action: EndNote 20 (Windows) find duplicates [Video]. YouTube. https://www.youtube.com/watch?v=30hO68w0C-4