# Crossref API: Get citation

> Gets a formatted citation and publication details for the best-matching Crossref work by title or DOI. Optional author and year help choose among similar works; citations reflect the metadata deposited with Crossref.

Unofficial. Not affiliated with or endorsed by Crossref.

- Page: https://fous.com/methods/crossref.org/get-citation
- Method: `crossref.org/get_citation`, version 1
- Website: crossref.org
- Returns: title, authors, journal or publisher, volume, issue, pages, year, type, DOI, formatted citation
- Effect: read (it gets data and changes nothing)
- Sign-in: none needed
- Cost: 1 credit per completed run (1¢ with pay as you go); failed runs are free
- Verified: Nov 2, 2026

## Inputs

| Field | Type | Required | In the run below | Description |
|---|---|---|---|---|
| `work` | string | yes | `"The Structure of Scientific Revolutions"` | Paper or book title or DOI, for example The Structure of Scientific Revolutions or 10.1038/nrd842. |
| `year` | integer | no | `2012` | Publication year to help select a work, for example 1996. |
| `style` | string | no | `"chicago"` | Citation style, for example mla. One of "apa", "mla", "chicago", "harvard", "ieee", "vancouver". Default "apa". |
| `author` | string | no | `"Thomas S. Kuhn"` | Author to help select a work, for example Thomas S. Kuhn. Default "". |

## Output

From a run on Oct 31, 2026. Its input:

```json
{
  "work": "The Structure of Scientific Revolutions",
  "year": 2012,
  "style": "chicago",
  "author": "Thomas S. Kuhn"
}
```

Its output:

```json
{
  "doi": "10.7208/chicago/9780226458144.001.0001",
  "type": "book",
  "year": 2012,
  "issue": null,
  "pages": null,
  "title": "The Structure of Scientific Revolutions",
  "volume": null,
  "authors": [
    "Thomas S. Kuhn",
    "Ian Hacking"
  ],
  "citation": "Kuhn, Thomas S., and Ian Hacking. The Structure of Scientific Revolutions. University of Chicago Press, 2012. https://doi.org/10.7208/chicago/9780226458144.001.0001.",
  "doi_link": "https://doi.org/10.7208/chicago/9780226458144.001.0001",
  "journal_or_publisher": "University of Chicago Press"
}
```

## Run it

From code, with a Fous API key in `FOUS_API_KEY`; the answer's `data` holds the output:

```bash
curl https://api.fous.com/v1/runs \
  -H "Authorization: Bearer $FOUS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"method":"crossref.org/get_citation","input":{"work":"The Structure of Scientific Revolutions","year":2012,"style":"chicago","author":"Thomas S. Kuhn"}}'
```

From an AI agent connected to the Fous MCP server: its `run` with the same method and input. To connect one, give it `set up https://fous.com/SKILL.md`.

## Ask your agent

- Can you give me an APA citation for the paper with DOI 10.1126/science.1225829?
- I need an MLA reference for "Attention Is All You Need" by Vaswani, 2017 — include volume and pages if there are any.
- Look up "Deep residual learning for image recognition" on Crossref and format it in IEEE style.
- Format a Vancouver-style reference for the 2001 Nature paper on the initial sequencing and analysis of the human genome.
- Pull the Chicago citation from crossref.org for Mayr's "The Growth of Biological Thought" (1982), with publisher and year.

## Input schema

```json
{
  "type": "object",
  "required": [
    "work"
  ],
  "properties": {
    "work": {
      "type": "string",
      "description": "Paper or book title or DOI, for example The Structure of Scientific Revolutions or 10.1038/nrd842."
    },
    "year": {
      "type": "integer",
      "description": "Publication year to help select a work, for example 1996."
    },
    "style": {
      "enum": [
        "apa",
        "mla",
        "chicago",
        "harvard",
        "ieee",
        "vancouver"
      ],
      "type": "string",
      "default": "apa",
      "description": "Citation style, for example mla."
    },
    "author": {
      "type": "string",
      "default": "",
      "description": "Author to help select a work, for example Thomas S. Kuhn."
    }
  },
  "additionalProperties": false
}
```

## Output schema

```json
{
  "type": "object",
  "required": [
    "title",
    "authors",
    "journal_or_publisher",
    "volume",
    "issue",
    "pages",
    "year",
    "type",
    "doi",
    "doi_link",
    "citation"
  ],
  "properties": {
    "doi": {
      "type": "string"
    },
    "type": {
      "type": [
        "string",
        "null"
      ]
    },
    "year": {
      "type": [
        "integer",
        "null"
      ]
    },
    "issue": {
      "type": [
        "string",
        "null"
      ]
    },
    "pages": {
      "type": [
        "string",
        "null"
      ]
    },
    "title": {
      "type": [
        "string",
        "null"
      ]
    },
    "volume": {
      "type": [
        "string",
        "null"
      ]
    },
    "authors": {
      "type": "array",
      "items": {
        "type": "string"
      }
    },
    "citation": {
      "type": "string"
    },
    "doi_link": {
      "type": "string"
    },
    "journal_or_publisher": {
      "type": [
        "string",
        "null"
      ]
    }
  },
  "additionalProperties": false
}
```

## See more

- [NIH API: Get PubMed article](https://fous.com/methods/pubmed.ncbi.nlm.nih.gov/get-article.md): Gets the full PubMed abstract and publication details for one article by title, PubMed link, or PubMed number (PMID). A title is searched in PubMed titles first and must closely match a found article. Some articles have no abstract or free full text.
- [Semantic Scholar API: Get paper details](https://fous.com/methods/semanticscholar.org/get-paper.md): Finds a paper on Semantic Scholar by title, DOI or Semantic Scholar link and returns its abstract, one-sentence summary, authors, publication details, citation counts and a free PDF link when there is one.
- [arXiv API: Get paper](https://fous.com/methods/arxiv.org/get-paper.md): Gets an arXiv paper's title, authors, abstract, subjects, submission dates and publication details from its exact title, arXiv link or number.
- [Poetry Foundation API: Get poem by title](https://fous.com/methods/poetryfoundation.org/get-poem.md): Finds a poem on Poetry Foundation by title (optionally by poet) and returns its full public text, poet, printed source, publication year and subject tags.
- [Unpaywall API: Get free version of a paper](https://fous.com/methods/unpaywall.org/get-free-version.md): Finds a legal free copy of a paper by title or DOI, with its best available link and other copies. If no free copy is indexed, the copy links are null.
- [ORCID API: Get researcher profile](https://fous.com/methods/orcid.org/get-researcher.md): Looks up a researcher's public ORCID profile by name or ORCID iD, with employment, education, funding and up to 100 works. An institution helps tell namesakes apart; private entries are left out.
- [OpenAlex API: Search scholarly papers](https://fous.com/methods/openalex.org/search-papers.md): Searches OpenAlex scholarly works by topic, with optional institution, publication-year and open-access filters, ranked by relevance, citations or newest date.
- [Semantic Scholar API: Get researcher impact metrics](https://fous.com/methods/semanticscholar.org/get-author.md): Finds a Semantic Scholar author by name (optionally limited to a listed institution), picks the best-cited matching profile and returns their impact metrics and up to 10 most-cited papers.