It depends on why the books is rare, some books are rare because they are not popular while other because they were banned. For example I know a novel were the English translation is easily available, but the original language is rare because it was banned in the original language in multiple countries. Don’t forget collecter artbooks that were never digitised.
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It depends on why the books is rare, some books are rare because they are not popular while other because they were banned. For example I know a novel were the English translation is easily available, but the original language is rare because it was banned in the original language in multiple countries.