https://en.wikipedia.org/wiki/School_shooting#Europe
https://worldpopulationreview.com/country-rankings/school-shootings-by-country
https://www.msn.com/en-us/video/tunedin/us-school-shootings-in-2021-by-the-numbers/vi-AARrums
https://www.edweek.org/leadership/school-shootings-this-year-how-many-and-where/2021/03
https://www.history.com/this-day-in-history/gunman-kills-students-and-adults-at-newtown-connecticut-elementary-school
https://www.history.com/this-day-in-history/massacre-at-virginia-tech-leaves-32-dead