Photograph credits

• ShakataGaNai, CC BY-SA 3.0
• Robert.Harker, CC BY-SA 3.0
• Fabienne Serriere, CC BY-SA 3.0
• Helpameout, CC BY-SA 3.0
• The National Archives (UK), CC BY 3.0
• Jakub T. Jankiewicz, CC BY-SA 4.0
• www.heimnetzwerke.net, CC BY 4.0
• Lenharth Systems, CC0
• Jacek Halicki, CC BY-SA 4.0