# External source check (ABT-GUARD-20260831)

Checked 2026-09-04 with `scripts/verify-external-sources.py` (GET, follow redirects, 25s timeout). None of these pages audited this fixture. Machine log: [`external-source-check-ABT-GUARD-20260831.json`](./external-source-check-ABT-GUARD-20260831.json).

| Source | Requested URL | Final URL | HTTP | Title SHA-256 | Note | Use |
|---|---|---|---|---|---|---|
| Statement on Statistical Significance and P-Values | https://www.amstat.org/asa/files/pdfs/p-valuestatement.pdf | https://www.amstat.org/asa/files/pdfs/p-valuestatement.pdf | 200 | — |  | Interpretation limits for p-values |
| e-Handbook of Statistical Methods | https://www.itl.nist.gov/div898/handbook/ | https://www.itl.nist.gov/div898/handbook/ | 200 | d4a4bc3e6e009d42 |  | Experimental-design and statistical-method reference |
| Advertising Substantiation | https://www.ftc.gov/legal-library/browse/advertising-marketing/advertising-substantiation | https://www.ftc.gov/legal-library/browse/advertising-marketing/advertising-substantiation | 404 | 3a691ca189085929 | http 404 | Evidence expectations for advertising claims |
| AI Index | https://hai.stanford.edu/ai-index | https://hai.stanford.edu/ai-index | 200 | e0c150f96e7fccab |  | AI adoption context, not experiment validation |
| AI RMF | https://www.nist.gov/itl/ai-risk-management-framework | https://www.nist.gov/itl/ai-risk-management-framework | 200 | 274a251954063e95 |  | AI risk-management context |

Keep original requested URLs. Re-check at decision time.