Black Bullets, “Seized Enemy Material Used by permission of the Alien Property Custodian in the public interest”, “Exclusive for the Men and Women of American Industry”, “Official War Film Number 55”,
“US Department of the Army, 1945. Cpatured German and Japanese footage shows how enemy mined coal with slave labor. Importance of miner in war strategy of armies that move on coal-dependent vehicles, planes, and ships”