Start with the principle
What you need to know
Duplicates are not always identical. The same source can appear twice with different author initials, page ranges, URLs or DOI formats.
A practical method
Check it step by step
- 01
Normalise obvious differences
Ignore superficial differences such as https://doi.org/ versus DOI labels while comparing identity.
- 02
Compare core fields
Check author, year, title and publication together.
- 03
Keep the most complete entry
Retain the record that accurately reflects the source and required style.
- 04
Repair citation links
Ensure citations now point to the single retained entry or number.
Apply the guidance
Examples
Patel, S. I. (2025)… doi:10.1234/example and Patel, S. (2025)… https://doi.org/10.1234/example
Before submission
Final checklist
- DOI compared
- Title compared
- Author order compared
- Correct version retained
- Numeric citations renumbered if required
Course, university and publisher requirements vary. Confirm final punctuation, capitalisation and presentation against the guide you have been instructed to use.