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In 1955, Guinness World Records began maintaining a list of the verified oldest people. It developed into a list of all supercentenarians whose lifespan had been verified by at least three documents, in a standardized process, according the norms of modern longevity research. Many unverified cases ("claims" or "traditions") have been controverted by reliable sources. Taking reliable demographic data into account, these unverified case vary widely in their plausibility.
Read more about this topic: Longevity Claims