https://www.cfr.org/backgrounder/yemen-crisis
https://www.bbc.com/news/world-middle-east-29319423
https://commons.wikimedia.org/wiki/File:Yemeni_Civil_War.svg
https://en.wikipedia.org/wiki/Yemeni_Civil_War_(2014%E2%80%93present)
https://en.wikipedia.org/wiki/Saudi_Arabian-led_intervention_in_Yemen