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2. Al Jazeera. 2022. “Saudi Aramco’s Jeddah Oil Depot Hit by Houthi Attack.” Al Jazeera. March 25. https://www.aljazeera.com/news/2022/3/25/saudi-aramco-jeddah-storage-facility-hit-by-attack.
3. Amos, Owen. 2020. “Why Are Chinese Fishermen Finding So Many ‘Submarine Spies’?” BBC, January 16. https://www.bbc.com/news/world-asia-china-51130644.
4. AUVSI. 2021. “2021 Defense Budget for Unmanned Systems and Robotics.” https://www.auvsi.org/sites/default/files/PDFs/AUVSI%20Executive%20Summary%20-%202021%20Defense%20Budget%20for%20Unmanned%20Systems%20and%20Robotics.pdf.
5. AUVSI, 2022. “Department of Defense Unmanned Systems Budget Report.” https://www.auvsi.org/2022-dod-budget-report