New answers tagged copyright
It appears that I found the answer. Such photographs are not copyrightable in the USA, but the situation may be different in other countries. https://en.wikipedia.org/wiki/Bridgeman_Art_Library_v._Corel_Corp. http://englishhistory.net/tudor/art.html From the second link, The Bridgeman Art Library had made photographic reproductions of famous works ...
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