https://www.wearethemighty.com/popular/the-18-greatest-fighter-aircraft-of-all-time/
https://archive.org/details/in.ernet.dli.2015.284794/page/n361/mode/2up?view=theater
https://archive.org/details/sopwithcamelvsfo0000gutt/page/10/mode/2up?view=theater
https://autojournalism.com/top-10-most-successful-u-boats-of-world-war-ii/#1_U-48_u-boat_WW2
https://archive.org/details/fipslegendaryubo0000furb/page/78/mode/2up?view=theater&q=UC+II
https://archive.org/details/defenseagainstga00unit/page/18/mode/2up?q=PHOSGENE&view=theater
https://archive.org/details/DTIC_ADA090453
https://archive.org/details/handbookmaximau00deptgoog/page/n22/mode/2up?view=theater
https://emergency.cdc.gov/agent/phosgene/basics/facts.asp
https://uboat.net/wwi/boats/?boat=UC+65
https://www.realhistoryonline.com/articles/maxim-machine-gun-pm1910/
https://medium.com/war-is-boring/maxims-machine-gun-slaughtered-hundreds-of-thousands-of-people-f9e068f5148