20480
Commercial airline service is provided out of Houston from William P. Hobby Airport and George Bush Intercontinental Airport , both in Houston .
 Houston, William P. Hobby Airport, George Bush Intercontinental Airport, Houston
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Houston, William P. Hobby Airport, George Bush Intercontinental Airport, Houston