Included photos are public domain, by the following authors:

- Anthony Cantin
- Dlanor S
- John Towner
- Lance Asper
- Luca Bravo
- Maciek Krawiec
- Nicki Eliza Schinow
- Oliver Plattner
- Pathum Danthanarayana
- Pierre Châtel-Innocenti
- Rawpixel
- Ryan Stone
- Trevor Cole
