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An estimated 13 - 20 million men , women , and children from over 50 developing countries are directly engaged in the artisanal mining sector Issues in Artisanal Mining Artisanal mining can include activities as simple as panning for gold in rivers , to as complex as development of underground workings and small-scale processing plants .
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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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