This is a retouched picture, which means that it has been digitally altered from its original version. Modifications: image restoration. The original can be viewed here: Marie Curie c. 1920s - original.jpg: .
Assessment
This is a featured picture on the English language Wikipedia (Featured pictures) and is considered one of the finest images. See its nomination here.
If you think this file should be featured on Wikimedia Commons as well, feel free to nominate it.
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The author died in 1947, so this work is in the public domain in its country of origin and other countries and areas where the copyright term is the author's life plus 75 years or fewer.