37806
For example , the first pair emitted by the source might be " ( + " z " , − " x " ) to Alice and ( − " z " , + " x " ) to Bob " , the next pair " ( − " z " , − " x " ) to Alice and ( + " z " , + " x " ) to Bob " , and so forth .
 Alice, Bob
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Alice, Bob