following user names refer to nl.wikipedia. Ruimtehoek Vanaf Franse Wikipedia (Angle solide definition.png): Surface délimitée par la projection d'un quadrilatère...
choice. This image is a derivative work of the following images: File:Ruimtehoek.png licensed with Cc-by-sa-3.0-migrated, GFDL 2006-02-05T14:36:40Z Maksim...
