The three isotopes of hydrogen. Image by Lamiot for french version, from Dirk Hünniger [GFDL (http://www.gnu.org/copyleft/fdl.html), via Wikimedia Commons.
Norwegian volunteers in battle gear, somewhere in Northern Finland. (Jan. 1940). Operation Gunnerside members wore similar attire. Photo Credit: [Public domain], via Wikimedia Commons.
Bridge to Vemork Plant. Photo by martin_vmorris (Norsk Hydro power plant, Rjukin, Norway), via Wikimedia Commons.