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The blast occurred as workers were unloading a coolant used for steam generators at the Muskingum River plant said Melissa McHenry a spokeswoman for  American Electric Power  based in Columbus  Ohio  .
 American Electric Power, Ohio
Please list all entity pairs containing a certain relationship in the given options.Output format is "word1, word2; word3, word4". 
Option: cities of residence, top members employees, members, alternate names, origin, state or provinces of residence, title of person, spouse, city of headquarters, NA, founded by, state or province of headquarters, employee of, countries of residence, country of birth, founded, subsidiaries, country of headquarters 
Text: {0} 
Answer:
 American Electric Power, Ohio