41352
In 2008 , the origins of the Celts were attributed to this period by John T. Koch and supported by Barry Cunliffe .
 John T. Koch, Barry Cunliffe
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 John T. Koch, Barry Cunliffe