Different legal foundations
A public-domain work is not restricted by copyright in the relevant jurisdiction. CC BY applies to copyrighted material and grants broad permission under enforceable attribution conditions.
Why location and source matter
Public-domain status can vary by country, and a modern scan, edition, translation, recording, or photograph can have separate rights. CC BY offers a stated license, but only from a person who controls the relevant rights.
Practical recordkeeping
For public-domain material, document the status rationale and source. For CC BY material, preserve the creator, title, source, license version, and modification history.
Put it into practice
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