106055
After brief post-doc positions at SLAC and Caltech , he went to CERN and has held an indefinite contract there since 1978 .
 SLAC, Caltech, CERN
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 SLAC, Caltech, CERN