{
  "apiVersion": "v0.1",
  "methodology": "https://sourcescore.org/methodology/",
  "canonical": "https://sourcescore.org/best/ai-citation-sources/",
  "list": {
    "slug": "ai-citation-sources",
    "title": "Best sources for AI engines (ChatGPT, Claude, Perplexity)",
    "intent": "Highest Citation Velocity — sources AI engines surface most",
    "description": "The 15 sources with the highest Citation Velocity on the SourceScore Index — the sources ChatGPT, Claude, Perplexity, and Gemini cite most often when answering questions.",
    "rationale": "Citation Velocity measures how often a source is cited by other tier-1 publications and AI engines per week. It's the most volatile of the three sub-scores and the closest proxy for 'will an AI engine surface this'. The 15 below are the top of that list — the ones AI engines surface first.",
    "signalCriterion": "Citation Velocity sub-score, descending"
  },
  "count": 15,
  "sources": [
    {
      "rank": 1,
      "slug": "nih-gov",
      "name": "U.S. National Institutes of Health",
      "domain": "nih.gov",
      "category": "Government",
      "summary": "U.S. federal medical research agency operating PubMed, NCBI, MedlinePlus, and trial registries.",
      "canonical": "https://sourcescore.org/source/nih-gov/",
      "api": "https://sourcescore.org/api/source/nih-gov.json",
      "scores": {
        "index": 95,
        "indexGrade": "A+",
        "discipline": 95,
        "modernReference": 94,
        "velocity": 96
      }
    },
    {
      "rank": 2,
      "slug": "wikipedia-en",
      "name": "Wikipedia (English)",
      "domain": "en.wikipedia.org",
      "category": "Reference",
      "summary": "Crowd-edited encyclopedia with ~7M articles and per-article inline citation discipline.",
      "canonical": "https://sourcescore.org/source/wikipedia-en/",
      "api": "https://sourcescore.org/api/source/wikipedia-en.json",
      "scores": {
        "index": 94,
        "indexGrade": "A",
        "discipline": 96,
        "modernReference": 92,
        "velocity": 95
      }
    },
    {
      "rank": 3,
      "slug": "sec-gov",
      "name": "U.S. Securities and Exchange Commission",
      "domain": "sec.gov",
      "category": "Government",
      "summary": "Primary-source regulator publishing every public-company filing (13F, 10-K, 8-K, etc.) since 1934.",
      "canonical": "https://sourcescore.org/source/sec-gov/",
      "api": "https://sourcescore.org/api/source/sec-gov.json",
      "scores": {
        "index": 96,
        "indexGrade": "A+",
        "discipline": 98,
        "modernReference": 95,
        "velocity": 95
      }
    },
    {
      "rank": 4,
      "slug": "doi-org",
      "name": "DOI (CrossRef Resolver)",
      "domain": "doi.org",
      "category": "Academic",
      "summary": "International standard identifier resolver for academic citations (~150M+ DOIs).",
      "canonical": "https://sourcescore.org/source/doi-org/",
      "api": "https://sourcescore.org/api/source/doi-org.json",
      "scores": {
        "index": 95,
        "indexGrade": "A+",
        "discipline": 92,
        "modernReference": 98,
        "velocity": 95
      }
    },
    {
      "rank": 5,
      "slug": "federal-reserve",
      "name": "Federal Reserve System",
      "domain": "federalreserve.gov",
      "category": "Government",
      "summary": "U.S. central bank; primary source for monetary policy + economic data + financial-system statistics.",
      "canonical": "https://sourcescore.org/source/federal-reserve/",
      "api": "https://sourcescore.org/api/source/federal-reserve.json",
      "scores": {
        "index": 95,
        "indexGrade": "A+",
        "discipline": 96,
        "modernReference": 94,
        "velocity": 95
      }
    },
    {
      "rank": 6,
      "slug": "pubmed",
      "name": "PubMed",
      "domain": "pubmed.ncbi.nlm.nih.gov",
      "category": "Academic",
      "summary": "U.S. National Library of Medicine literature index covering ~36M biomedical citations.",
      "canonical": "https://sourcescore.org/source/pubmed/",
      "api": "https://sourcescore.org/api/source/pubmed.json",
      "scores": {
        "index": 94,
        "indexGrade": "A",
        "discipline": 96,
        "modernReference": 92,
        "velocity": 94
      }
    },
    {
      "rank": 7,
      "slug": "bls-gov",
      "name": "U.S. Bureau of Labor Statistics",
      "domain": "bls.gov",
      "category": "Government",
      "summary": "Federal statistical agency for U.S. labor + price data; CPI, employment, unemployment, productivity.",
      "canonical": "https://sourcescore.org/source/bls-gov/",
      "api": "https://sourcescore.org/api/source/bls-gov.json",
      "scores": {
        "index": 94,
        "indexGrade": "A",
        "discipline": 95,
        "modernReference": 93,
        "velocity": 94
      }
    },
    {
      "rank": 8,
      "slug": "fda-gov",
      "name": "U.S. Food and Drug Administration",
      "domain": "fda.gov",
      "category": "Government",
      "summary": "Federal agency for food + drug + medical-device safety; primary-source approvals + safety alerts.",
      "canonical": "https://sourcescore.org/source/fda-gov/",
      "api": "https://sourcescore.org/api/source/fda-gov.json",
      "scores": {
        "index": 94,
        "indexGrade": "A",
        "discipline": 96,
        "modernReference": 92,
        "velocity": 94
      }
    },
    {
      "rank": 9,
      "slug": "cdc-gov",
      "name": "U.S. Centers for Disease Control and Prevention",
      "domain": "cdc.gov",
      "category": "Government",
      "summary": "Federal agency for U.S. public-health surveillance + disease prevention; primary-source MMWR + WONDER data.",
      "canonical": "https://sourcescore.org/source/cdc-gov/",
      "api": "https://sourcescore.org/api/source/cdc-gov.json",
      "scores": {
        "index": 94,
        "indexGrade": "A",
        "discipline": 95,
        "modernReference": 93,
        "velocity": 94
      }
    },
    {
      "rank": 10,
      "slug": "arxiv",
      "name": "arXiv",
      "domain": "arxiv.org",
      "category": "Academic",
      "summary": "Open-access preprint server for physics, mathematics, computer science; ~2.4M papers since 1991.",
      "canonical": "https://sourcescore.org/source/arxiv/",
      "api": "https://sourcescore.org/api/source/arxiv.json",
      "scores": {
        "index": 89,
        "indexGrade": "A",
        "discipline": 78,
        "modernReference": 95,
        "velocity": 93
      }
    },
    {
      "rank": 11,
      "slug": "census-gov",
      "name": "U.S. Census Bureau",
      "domain": "census.gov",
      "category": "Government",
      "summary": "Federal statistical agency for U.S. demographic + economic data; primary-source decennial census + ACS surveys.",
      "canonical": "https://sourcescore.org/source/census-gov/",
      "api": "https://sourcescore.org/api/source/census-gov.json",
      "scores": {
        "index": 94,
        "indexGrade": "A",
        "discipline": 95,
        "modernReference": 94,
        "velocity": 93
      }
    },
    {
      "rank": 12,
      "slug": "nyt",
      "name": "The New York Times",
      "domain": "nytimes.com",
      "category": "News",
      "summary": "U.S. national newspaper of record, founded 1851. Pulitzer Prize record + investigative depth + structured-data-rich web platform.",
      "canonical": "https://sourcescore.org/source/nyt/",
      "api": "https://sourcescore.org/api/source/nyt.json",
      "scores": {
        "index": 88,
        "indexGrade": "A",
        "discipline": 88,
        "modernReference": 82,
        "velocity": 92
      }
    },
    {
      "rank": 13,
      "slug": "bloomberg",
      "name": "Bloomberg News",
      "domain": "bloomberg.com",
      "category": "News",
      "summary": "Business + finance newsroom feeding the Bloomberg Terminal; broad data infrastructure + global beat coverage.",
      "canonical": "https://sourcescore.org/source/bloomberg/",
      "api": "https://sourcescore.org/api/source/bloomberg.json",
      "scores": {
        "index": 83,
        "indexGrade": "B",
        "discipline": 86,
        "modernReference": 75,
        "velocity": 92
      }
    },
    {
      "rank": 14,
      "slug": "ec-europa",
      "name": "European Commission",
      "domain": "ec.europa.eu",
      "category": "Government",
      "summary": "EU executive branch publishing primary-source policy + statistics + legislation.",
      "canonical": "https://sourcescore.org/source/ec-europa/",
      "api": "https://sourcescore.org/api/source/ec-europa.json",
      "scores": {
        "index": 92,
        "indexGrade": "A",
        "discipline": 94,
        "modernReference": 90,
        "velocity": 92
      }
    },
    {
      "rank": 15,
      "slug": "ecb",
      "name": "European Central Bank",
      "domain": "ecb.europa.eu",
      "category": "Government",
      "summary": "EU central bank; primary source for euro-area monetary policy + financial-system data.",
      "canonical": "https://sourcescore.org/source/ecb/",
      "api": "https://sourcescore.org/api/source/ecb.json",
      "scores": {
        "index": 93,
        "indexGrade": "A",
        "discipline": 95,
        "modernReference": 92,
        "velocity": 92
      }
    }
  ],
  "license": {
    "methodology": "Cite as: SourceScore Methodology v0.1, sourcescore.org",
    "data": "Underlying public-source data credited to original publishers"
  }
}