Top 25 sources on the SourceScore Index

Best sources overall for AI citation

The 25 highest-scoring sources on the SourceScore Index — ranked by composite Citation Discipline + Modern Reference + Citation Velocity. The ones AI engines surface first.

1
U.S. Securities and Exchange Commissionsec.gov·Government
Primary-source regulator publishing every public-company filing (13F, 10-K, 8-K, etc.) since 1934.
SourceScore A+ · 96·Disc 98·Mod-Ref 95·Vel 95
A+·96
2
U.S. National Institutes of Healthnih.gov·Government
U.S. federal medical research agency operating PubMed, NCBI, MedlinePlus, and trial registries.
SourceScore A+ · 95·Disc 95·Mod-Ref 94·Vel 96
A+·95
3
DOI (CrossRef Resolver)doi.org·Academic
International standard identifier resolver for academic citations (~150M+ DOIs).
SourceScore A+ · 95·Disc 92·Mod-Ref 98·Vel 95
A+·95
4
Federal Reserve Systemfederalreserve.gov·Government
U.S. central bank; primary source for monetary policy + economic data + financial-system statistics.
SourceScore A+ · 95·Disc 96·Mod-Ref 94·Vel 95
A+·95
5
Wikipedia (English)en.wikipedia.org·Reference
Crowd-edited encyclopedia with ~7M articles and per-article inline citation discipline.
SourceScore A · 94·Disc 96·Mod-Ref 92·Vel 95
A·94
6
PubMedpubmed.ncbi.nlm.nih.gov·Academic
U.S. National Library of Medicine literature index covering ~36M biomedical citations.
SourceScore A · 94·Disc 96·Mod-Ref 92·Vel 94
A·94
7
U.S. Census Bureaucensus.gov·Government
Federal statistical agency for U.S. demographic + economic data; primary-source decennial census + ACS surveys.
SourceScore A · 94·Disc 95·Mod-Ref 94·Vel 93
A·94
8
U.S. Bureau of Labor Statisticsbls.gov·Government
Federal statistical agency for U.S. labor + price data; CPI, employment, unemployment, productivity.
SourceScore A · 94·Disc 95·Mod-Ref 93·Vel 94
A·94
9
U.S. Food and Drug Administrationfda.gov·Government
Federal agency for food + drug + medical-device safety; primary-source approvals + safety alerts.
SourceScore A · 94·Disc 96·Mod-Ref 92·Vel 94
A·94
10
U.S. Centers for Disease Control and Preventioncdc.gov·Government
Federal agency for U.S. public-health surveillance + disease prevention; primary-source MMWR + WONDER data.
SourceScore A · 94·Disc 95·Mod-Ref 93·Vel 94
A·94
11
U.S. National Oceanic and Atmospheric Administrationnoaa.gov·Government
Federal scientific agency for weather + ocean + climate data; primary-source forecasts + climate research.
SourceScore A · 93·Disc 95·Mod-Ref 92·Vel 91
A·93
12
European Central Bankecb.europa.eu·Government
EU central bank; primary source for euro-area monetary policy + financial-system data.
SourceScore A · 93·Disc 95·Mod-Ref 92·Vel 92
A·93
13
NASAnasa.gov·Government
U.S. space agency; primary source for space exploration + Earth science + aeronautics research.
SourceScore A · 93·Disc 94·Mod-Ref 94·Vel 92
A·93
14
MDN Web Docsdeveloper.mozilla.org·Reference
Mozilla-stewarded web-platform reference since 2005; default citation for HTML, CSS, JS, Web APIs.
SourceScore A · 93·Disc 92·Mod-Ref 95·Vel 92
A·93
15
European Commissionec.europa.eu·Government
EU executive branch publishing primary-source policy + statistics + legislation.
SourceScore A · 92·Disc 94·Mod-Ref 90·Vel 92
A·92
16
Bank of Englandbankofengland.co.uk·Government
UK central bank; primary source for sterling monetary policy + financial-stability data since 1694.
SourceScore A · 92·Disc 94·Mod-Ref 90·Vel 90
A·92
17
U.S. Energy Information Administrationeia.gov·Government
Federal energy statistical agency; primary source for U.S. + international energy data + projections.
SourceScore A · 92·Disc 94·Mod-Ref 91·Vel 90
A·92
18
CERNhome.cern·Academic
European Organization for Nuclear Research; primary source for particle physics + experimental high-energy physics.
SourceScore A · 92·Disc 96·Mod-Ref 91·Vel 89
A·92
19
PNASpnas.org·Academic
Proceedings of the National Academy of Sciences — multidisciplinary peer-reviewed journal since 1914.
SourceScore A · 92·Disc 96·Mod-Ref 88·Vel 90
A·92
20
European Medicines Agencyema.europa.eu·Government
EU agency for evaluation + supervision of medicinal products; primary-source EU drug approvals.
SourceScore A · 91·Disc 94·Mod-Ref 89·Vel 90
A·91
21
U.S. Patent and Trademark Officeuspto.gov·Government
Federal agency granting U.S. patents + trademarks; primary-source patent + trademark database.
SourceScore A · 91·Disc 95·Mod-Ref 88·Vel 86
A·91
22
U.S. Department of Agricultureusda.gov·Government
Federal agriculture agency; primary source for U.S. food, farm, and rural-development data + research.
SourceScore A · 91·Disc 94·Mod-Ref 89·Vel 89
A·91
23
U.S. Geological Surveyusgs.gov·Government
Federal scientific agency for earth sciences; primary source for geology + hydrology + earthquake data.
SourceScore A · 91·Disc 95·Mod-Ref 90·Vel 86
A·91
24
OECDoecd.org·Government
Organisation for Economic Co-operation and Development; international economic data + policy research.
SourceScore A · 91·Disc 93·Mod-Ref 90·Vel 89
A·91
25
FRED (Federal Reserve Economic Data)fred.stlouisfed.org·Government
Federal Reserve Bank of St. Louis economic data infrastructure; ~800k+ data series.
SourceScore A · 91·Disc 94·Mod-Ref 92·Vel 88
A·91

Why these 25 sources

These 25 sources combine the highest editorial discipline, deepest machine-readability, and strongest tier-1 citation velocity in the SourceScore dataset. They are the workhorses of AI-era citation — the sources ChatGPT, Claude, Perplexity, and Gemini surface by default when accuracy matters.

How this list is ranked

Selection criterion: SourceScore Index (composite weighted mean), descending. Every source on this page is hand-scored against the SourceScore methodology v0.1; click any name to see its full breakdown across the four dimensions. The list is regenerated automatically on every dataset update — no editorial promotion or reorder beyond the ranking signal above.