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Summary
Quadric Cone.
Source: http://en.wikipedia.org/wiki/Image:Quadric_Cone.jpg
This image is ineligible for copyright and therefore is in the public domain, because it consists entirely of information that is common property and contains no original authorship.
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Quadric Cone. Source: http://en.wikipedia.org/wiki/Image:Quadric_Cone.jpg This image is ineligible for copyright and therefore is in the public domain, because it consists entirely of information that is common property and contains no original authorshi