Task
Organize research claims and the sources that support them.

Instructions
Build a source matrix for [QUESTION]. Use only the supplied sources: [SOURCES]. For each claim, record source, publication date, exact supporting passage in your own words, confidence, contradictions, and what remains unknown. Distinguish official fact, reported observation, inference, and anecdote.

Expected output
Claim matrix followed by a short evidence-bounded answer.

Checks
- Every claim has a source or is labeled inference.
- Dates are recorded.
- Conflicts are not silently resolved.