I have released this picture under CC0, the most liberal licensing terms possible. You may use it without any restrictions. You may even use it without attribution.
I have however two requests:
If you use the image, please mention my name Hanno Böck and if appropriate link to my web page at https://hboeck.de/
Write me an E-Mail with a short note why and how you used my image
These conditions are voluntary. You are not required to fulfill them and may still use my images without attribution and without contacting me.
Licensing
I, the copyright holder of this work, hereby publish it under the following license:
The person who associated a work with this deed has dedicated the work to the public domain by waiving all of their rights to the work worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law. You can copy, modify, distribute and perform the work, even for commercial purposes, all without asking permission.
http://creativecommons.org/publicdomain/zero/1.0/deed.enCC0Creative Commons Zero, Public Domain Dedicationfalsefalse