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Original document; first hand information on a topic or event; original research or thought.
Original creative works (art, music, poetry, etc.)
Results of scientific experiments
Results of clinical trials
First hand account of an event
Government records (births, census, deaths)
Sources that analyze, evaluate, interpret, describe, or criticize original documents.
- Critique of creative work
- Analysis, evaluation of research
- Review of results of the scientific experiments
- Analysis of results of clinical trials