license: This image is a derivative work of the following images: File:3D-Leveltorus.png licensed with PD-self 2007-01-03T11:34:19Z Kieff 700x700 (178222 Bytes)...
with POV-Ray. Illustrations for Morse Theory Derivative works of this file: 3D-Leveltorus-Reebgraph.png English determination method or standard: SHA-1...
