choice. This image is a derivative work of the following images: File:Conic_ref_syst.png licensed with Cc-by-sa-3.0-migrated, GFDL 2006-03-19T19:05:02Z Maksim...
of different reference systems for a conic section (ellipse). This is useful for a reduced equation of a conic section. It was created by me, Hynek...
