80636
Peterson is best known for creating the Dothraki and Valyrian languages for the HBO series Game of Thrones ( since 2009 ) and the Castithan and Irathient languages for Syfy 's Defiance ( since 2011 ) , but has been creating languages since 2000 .
 Peterson, HBO
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Peterson, HBO