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In March 2011 , plans were announced for the creation of PPL Center , an 8,500 - seat arena to be built in Allentown as the home for the Lehigh Valley Phantoms , the American Hockey League affiliate of the Philadelphia Flyers .
 PPL Center, Allentown, Lehigh Valley Phantoms, American Hockey League, Philadelphia Flyers
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 PPL Center, Allentown, Lehigh Valley Phantoms, American Hockey League, Philadelphia Flyers