Open the DOI record to read the deposited publication date, then check the publisher landing page for the online-first date, and use whichever date your citation style requires. A DOI (Digital Object Identifier) resolves through the Handle System to current information supplied for the identified object, commonly a landing page maintained by the registrant, so the DOI record and the publisher page can show different dates for the same article.
- Resolve the DOI to its landing page. Enter the DOI in a resolver or click the DOI link in the citation. Expected result: you reach the registrant's page for that specific article rather than a search results list.
- Read the deposited metadata for the DOI. A DOI lookup through the Crossref REST API returns the metadata deposited for that DOI, which includes the publication date recorded at deposit. Expected result: a specific date, not only the year printed in the citation.
- Check the publisher landing page for the online-first date. The article page often lists when the version of record first appeared online, separate from the issue date. Expected result: a second date you can compare with the deposited one.
- Match the date to your citation style. Citing Medicine provides structured rules and examples for citing journal articles and other publication types; follow the date element your style specifies. Expected result: one date chosen for a stated reason, such as the online-first date or the issue date.
If the two sources show different dates, record both and note which one your style calls for. A mismatch between the deposited date and the publisher page does not by itself show that either is wrong; it can reflect when metadata was deposited versus when the article appeared online. When the DOI does not resolve or the landing page omits a date, treat the date as unresolved and check the article PDF or the issue's table of contents before finalizing the reference.