This is a retouched picture, which means that it has been digitally altered from its original version. The original can be viewed here: Groetzsch-graph.svg: .
I, the copyright holder of this work, hereby publish it under the following licence:
Public domainPublic domainfalsefalse
I, the copyright holder of this work, release this work into the public domain. This applies worldwide. In some countries this may not be legally possible; if so: I grant anyone the right to use this work for any purpose, without any conditions, unless such conditions are required by law.
Original upload log
This image is a derivative work of the following images: