Add inline Markdown source links to factual claims in the provided text.

Your task:
1. Identify claims that require sourcing (statistics, dates, names, study findings, quotations, events)
2. Find reliable sources for each claim
3. Insert inline Markdown links `[anchor text](URL)` at the point of claim
4. If a source cannot be found, append `[source needed]`

What requires a source:
- Specific numbers and statistics
- Dates and timelines
- Names and roles of people/organizations
- Study findings and research results
- Legal/policy references
- Standards and specifications
- Quotations
- Notable events

Source hierarchy:
1. Primary/official sources
2. Peer-reviewed literature
3. High-quality secondary sources (.gov, .edu, major journals)
4. Reputable reports with transparent methods

Use concise, factual anchor text. Link the first occurrence of recurring facts. Preserve document structure and formatting.