Crossref Adapter

Implements ScholarlyDataSource for Crossref’s REST API. Cursor pagination for /works, and DOI-based lookups.

Highlights

• Cursor pagination via message.next-cursor
• Politeness: include mailto param and a descriptive User-Agent
• Search filters: year ranges, container-title, license flags
• Identifiers: DOIs normalized; author ORCIDs extracted when present

Search

$results = $crossref->searchWorks(Query::from([
    'q' => 'causal inference',
    'year' => '2015-2020',
    'limit' => 100,
]));

Lookup by DOI

$crossref->getWorkByDoi('10.1038/nature14539');

References/Citations

• References are available in work payloads when present; the adapter exposes listReferences() with provider support or emulation.
• Citations are limited in Crossref; the adapter provides best-effort lookups where feasible.

Configuration

• Set CROSSREF_MAILTO or a global mailto in scholarly.http.user_agent/providers.crossref.mailto.

Notes

• Crossref does not support author batch endpoints; the adapter no-ops unsupported features gracefully.