SourceScore
HIGHEST MODERN REFERENCE — OPEN-ACCESS + MACHINE-READABLE · BY VELOCITY

Best paywall-free sources for citation by Citation Velocity

Same 15 sources, re-sorted by Citation Velocity only — different signal than the composite Index. The leader changes: U.S. National Institutes of Health takes the top position at A+ · 96.

Leader by Velocity

U.S. National Institutes of Health leads best paywall-free sources for citation on Citation Velocity at A+ · 96

Velocity mean
92
Average Velocity across these 15 sources
Composite mean
93
Average SourceScore Index across the same 15 sources
Δ vs composite
-1
These sources score lower on Velocity than overall
Same list, different signal
Composite Index (default)By DisciplineBy Modern Reference
  1. 1
    U.S. National Institutes of Healthnih.gov↑4

    U.S. federal medical research agency operating PubMed, NCBI, MedlinePlus, and trial registries.

    Velocity A+ · 96·Index A+ · 95·Government
    A+·96
  2. 2
    DOI (CrossRef Resolver)doi.org↓1

    International standard identifier resolver for academic citations (~150M+ DOIs).

    Velocity A+ · 95·Index A+ · 95·Academic
    A+·95
  3. 3
    U.S. Securities and Exchange Commissionsec.gov↓1

    Primary-source regulator publishing every public-company filing (13F, 10-K, 8-K, etc.) since 1934.

    Velocity A+ · 95·Index A+ · 96·Government
    A+·95
  4. 4
    Federal Reserve Systemfederalreserve.gov↑3

    U.S. central bank; primary source for monetary policy + economic data + financial-system statistics.

    Velocity A+ · 95·Index A+ · 95·Government
    A+·95
  5. 5
    Wikipedia (English)en.wikipedia.org↑6

    Crowd-edited encyclopedia with ~7M articles and per-article inline citation discipline.

    Velocity A+ · 95·Index A · 94·Reference
    A+·95
  6. 6
    U.S. Bureau of Labor Statisticsbls.gov↑3

    Federal statistical agency for U.S. labor + price data; CPI, employment, unemployment, productivity.

    Velocity A · 94·Index A · 94·Government
    A·94
  7. 7
    U.S. Centers for Disease Control and Preventioncdc.gov↑3

    Federal agency for U.S. public-health surveillance + disease prevention; primary-source MMWR + WONDER data.

    Velocity A · 94·Index A · 94·Government
    A·94
  8. 8
    PubMedpubmed.ncbi.nlm.nih.gov↑4

    U.S. National Library of Medicine literature index covering ~36M biomedical citations.

    Velocity A · 94·Index A · 94·Academic
    A·94
  9. 9
    U.S. Food and Drug Administrationfda.gov↑5

    Federal agency for food + drug + medical-device safety; primary-source approvals + safety alerts.

    Velocity A · 94·Index A · 94·Government
    A·94
  10. 10
    arXivarxiv.org↓7

    Open-access preprint server for physics, mathematics, computer science; ~2.4M papers since 1991.

    Velocity A · 93·Index A · 89·Academic
    A·93
  11. 11
    U.S. Census Bureaucensus.gov↓5

    Federal statistical agency for U.S. demographic + economic data; primary-source decennial census + ACS surveys.

    Velocity A · 93·Index A · 94·Government
    A·93
  12. 12
    MDN Web Docsdeveloper.mozilla.org↓8

    Mozilla-stewarded web-platform reference since 2005; default citation for HTML, CSS, JS, Web APIs.

    Velocity A · 92·Index A · 93·Reference
    A·92
  13. 13
    NASAnasa.gov↓5

    U.S. space agency; primary source for space exploration + Earth science + aeronautics research.

    Velocity A · 92·Index A · 93·Government
    A·92
  14. 14
    U.S. National Oceanic and Atmospheric Administrationnoaa.gov↑1

    Federal scientific agency for weather + ocean + climate data; primary-source forecasts + climate research.

    Velocity A · 91·Index A · 93·Government
    A·91
  15. 15
    Semantic Scholarsemanticscholar.org↓2

    AI-powered academic search engine by Allen Institute for AI; ~200M+ papers indexed.

    Velocity B · 72·Index B · 83·Academic
    B·72

Why this ranking is different

The composite SourceScore Index averages all three sub-scores — Citation Discipline, Modern Reference, and Citation Velocity. This page surfaces the SAME source pool but ranks ONLY by Citation Velocity. The biggest re-shuffle: Wikipedia (English) jumps 6 positions vs the composite Index ranking.

Use this view when citation velocity is the signal that matters for your citation decision. The composite Index is the safer default; this dim-faceted view is the precision lens.