Messstation für Stickoxid am Theodor-Heuss-Ring
Habitator terrae (<a class="external free" href="https://commons.wikimedia.org/wiki/User:Habitator_terrae">https://commons.wikimedia.org/wiki/User:Habitator_terrae</a>)
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>