# Why are my reference counts lower than expected?

A work's `referenced_works` list can be shorter than the reference list you see in its PDF or Crossref record. That's expected, and it comes down to how OpenAlex builds citations: it lists a reference only when it can match it to another work already in OpenAlex.

The usual reasons a reference doesn't appear:

- The cited work isn't in OpenAlex, so there's nothing to link to.
- The source record's references differ from the final published PDF.
- The source record includes no references, and PDF parsing missed some.
- The reference has no DOI, so metadata-only matching didn't find it.

For the full explanation of how citation and reference data is built, see [Citations](/docs/citations/) in the docs.