261704
Japan maintains that , although the Chunxiao gas field rigs are on the PRC side of a median line that it regards as the two sides ' sea boundary , China may tap into a field that stretches underground into disputed areas .
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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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