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The history of weapons control has also included treaties to limit effective defense against weapons of mass destruction in order to preserve the determent doctrine of mutually assured destruction ( Anti-Ballistic Missile Treaty ) as well as treaties to limit the spread of nuclear technologies geographically ( African Nuclear Weapons Free Zone Treaty , Nuclear Non-Proliferation Treaty ) .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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