/opencitations/works/citations

POST /api/opencitations/works/citations

Price: 5 credits

List the citations pointing at one work. Each result is a single citation link with its own OpenCitations identifier, the identifiers of the citing and cited work, the date the citing work appeared, the interval between the two publications, and whether the pair is a journal or author self-citation

How to use it

A work the index does not cover and a work nothing cites both come back empty, so read an empty result as 'no citations recorded' rather than as a wrong identifier — confirm the work exists with /opencitations/works. When only the size matters, /opencitations/works/citation-count answers it without the list. `timespan` is an ISO 8601 duration and is negative when the citing work was published first, which happens with preprints. On a heavily cited work the default row order varies between identical calls, so a `count` smaller than the citation count returns a different slice each time — pass `sort_by` to make the order and the slice reproducible.

Parameters

• access-token string required

Request body

• timeout integer — Max scrapping execution timeout (in seconds) (default: 300; min: 20; max: 1500)
• created_in string nullable — Keep only edges whose creation date starts with this text, so `2020` takes a whole year and `2020-03` one month (examples: "2020", "2020-03"; minLength: 1)
• is_journal_self_citation boolean nullable — Keep only edges where the citing and cited work appeared in the same journal, or only those where they did not
• is_author_self_citation boolean nullable — Keep only edges where the citing and cited work share at least one author, or only those where they share none
• require array nullable — Drop edges that state no value for these fields (one of: "creation", "timespan")
• sort_by string nullable — Field to order the edges by (one of: "creation", "timespan", "oci")
• sort_order string nullable — Order direction, ascending unless stated (one of: "asc", "desc")
• id string required — Identifier of the cited work: a DOI, PubMed id, OpenAlex id or OpenCitations Meta id, written with its prefix. A plain DOI or a doi.org address is accepted too (examples: "doi:10.1038/nature12373", "pmid:23903748", "omid:br/06120344846", "openalex:W2159974629"; minLength: 1)
• count integer required — Number of citations to return (examples: 100; min: 1)

Response

• @type string (default: "OpenCitationsCitation")
• oci string required
• citing object nullable
  • @type string (default: "OpenCitationsWorkRef")
  • omid string nullable
  • doi string nullable
  • pmid string nullable
  • pmcid string nullable
  • openalex string nullable
  • other_ids array (default: [])
• cited object nullable
  • @type string (default: "OpenCitationsWorkRef")
  • omid string nullable
  • doi string nullable
  • pmid string nullable
  • pmcid string nullable
  • openalex string nullable
  • other_ids array (default: [])
• creation_date string nullable
• timespan string nullable
• is_journal_self_citation boolean nullable
• is_author_self_citation boolean nullable

Errors

• 422 — The request body did not validate Check the fields against this schema. A URN with the wrong prefix is the most common cause.
• 408 — The request ran past its time limit Raise `timeout` in the request body, up to the maximum this endpoint documents. Lowering `count` or turning off the `with_*` flags also helps, because less work finishes sooner.
• 412 — The entity was not found, or a precondition failed Retrying will not help: either the entity does not exist, or the input points at a different one.
• 429 — Too many requests: a rate limit or a usage window is exhausted When the response carries an X-Retry-After header, wait that many seconds and retry: the same number is in the body as `detail.retry_after`, and the limit clears once that window passes. The message in the body names the limit that was hit.
• 500 — Something broke on our side Retrying will not help. If it keeps happening, send us the X-Request-ID from the response headers.
• 529 — Rate limit reached, or the endpoint is overloaded Wait at least 30 seconds, then retry.

Response headers

• X-Error — Error message text (present only on error)
• X-Request-ID — Unique request identifier
• X-Execution-Time — Execution time in seconds
• X-Result-Count — How many records the body carries. 0 means an empty result, which is a normal answer and not by itself an error. A non-zero count can come back together with X-Error when the failure happened partway through — read this header and X-Error independently.
• X-Total-Available-Results — How many records exist for this query, when the endpoint can say. On a `dry_run` request this is the answer and the body is empty. It saturates: the endpoint's documented maximum means 'at least that many', any smaller number is exact.
• X-Warning — Present when the request body carried keys this endpoint does not document. They were ignored, so any filter you meant to apply through them did not apply. Check the spelling against this schema and retry.
• X-Retry-After — Seconds to wait before retrying. Present only on 429.