computer generated image of an alembic produced by Peter Stuart and released under an open content licence.  
<a rel="nofollow" class="external free" href="http://www.geocities.com/CollegePark/4206/graphics.html">http://www.geocities.com/CollegePark/4206/graphics.html</a>
The original uploader was <a href="https://en.wikipedia.org/wiki/User:Jeremiah" class="extiw" title="wikipedia:User:Jeremiah">Jeremiah</a> at <a href="https://en.wikipedia.org/wiki/" class="extiw" title="wikipedia:">English Wikipedia</a>.
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Transferred from <span class="plainlinks"><a class="external text" href="https://en.wikipedia.org">en.wikipedia</a></span> to Commons by <a href="//commons.wikimedia.org/wiki/User:Aboalbiss" title="User:Aboalbiss">aboalbiss</a>.