25169
In the case of a charged ( Reissner–Nordström ) or rotating ( Kerr ) black hole , it is possible to avoid the singularity .
 Reissner–Nordström, Kerr
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Reissner–Nordström, Kerr