collapse.png - Deutsches Bundesarchiv (CC-BY-SA 3.0)
maglev.png - Saruno Hirobano (CC-BY-SA 4.0)
highfactory.png - Cards84664 (CC-BY-SA 4.0)
ravenfield.png - Colin (CC-BY-SA 4.0)
elvon.png - IqRS (public domain)
protest.png - VargaA (CC-BY-SA 4.0), modified by Valixor
fog.png - Glg (CC-BY-SA 2.0)
summit2.png - duma.gov.ru (CC-BY 4.0)
military.png - Jonathan Mallard (CC-BY 2.0)
taneraw.png - Nikolau (CC-BY-SA 3.0)