image is a derivative work of the following images: File:Concavo_3.svg licensed with Cc-by-sa-3.0,2.5,2.0,1.0, GFDL 2007-10-01T17:42:50Z AnyFile 600x480...
original. https://creativecommons.org/licenses/by-sa/3.0CC BY-SA 3.0 Creative Commons Attribution-Share Alike 3.0 truetrue You may select the license of your...