Check that a source exists and supports the claim.
A plausible-looking book title or URL may be invented. Check the organisation, publication, date and the actual passage. A real source may still be cited for something it does not say. If a link fails, do not invent its contents; find another accessible reliable source or leave the claim unresolved.
Notebook: write your corrected or unresolved conclusion, the evidence you actually checked, and a reflection. Do not include passwords, identity documents or private information. Original BrainCheck companion content, BCAI-v1.