1. Cuff D. Anatomy of a disaster: the 1982 Caldecott Tunnel fire that killed seven. Mercury News. Available at: https://www.mercurynews.com/2013/10/29/anatomy-of-a-disaster-the-1982-caldecott-tunnel-fire-that-killed-seven/.
2. Truck explosion kills 3,000 in Afghanistan. History Channel. Available at: https://www.history.com/this-day-in-history/truck-explosion-kills-3000-in-afghanistan.
3. Syrian soldiers killed by rebel tunnel-bombs. Aljazeera. Available at: https://www.aljazeera.com/news/2014/7/29/syrian-soldiers-killed-by-rebel-tunnel-bombs.
4. 31 Dead, 9 Missing in Massive Highway Tunnel Explosion in China. 2014. Time. Available at: https://time.com/22880/31-dead-9-missing-in-massive-highway-tunnel-explosion-in-china/.
5. Sewer System Explosion in Calumet City Leaves Massive Crater. 2014. NBC-Chicago. Available at: https://www.nbcchicago.com/news/local/calumet-city-crater/1978211/.