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In a filing with the Securities and Exchnage Commission , Buffett said he bought 62,900 additional common shares of the Boston-based real estate investment trust at prices ranging from $ 7.65 to $ 8.02 a share .
 Boston-based, Securities and Exchnage Commission, Buffett
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, else, organization, person 
Text: {0} 
Answer:
 Boston-based, Securities and Exchnage Commission, Buffett