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.