1. Agnew, John. “Territoriality/Territory.” in The Dictionary of Human Geography, edited by Ronald J. Johnston, 823–824. Oxford: Blackwell Publishers, 2000.
2. Almeida Alex and Michael Knights. “Breaking Point: Consolidating Houthi Military Setbacks in Yemen.” January 2022. Accessed September 5 2022. https://www.washingtoninstitute.org/policy-analysis/breaking-point-consolidating-houthi-military-setbacks-yemen.
3. Rebelocracy
4. Recruitment into Armed Groups in Colombia: A Survey of Demobilized Fighters
5. Armed Conflict Location and Event Data Project. “War in Yemen.” Accessed September 5 2022. https://acleddata.com/research-hub-war-in-yemen/.