This image was copied from en.wikipedia.org. The original description was:
Protactinium table image created by <a href="//commons.wikimedia.org/wiki/User:Schneelocke" title="User:Schneelocke">schnee</a>, <a href="//commons.wikimedia.org/wiki/June_22" title="June 22">June 22</a>, <a href="//commons.wikimedia.org/wiki/2003" title="2003">2003</a> for Wikipedia.
<a href="//commons.wikimedia.org/wiki/User:Ahoerstemeier" title="User:Ahoerstemeier">Ahoerstemeier</a>
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