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Jeffers was noted for the accuracy and precision of his work , which included extensive observations of double star s. During the war years , Jeffers served first at a radiation laboratory of the Massachusetts Institute of Technology , and then as an operations analyst in Alaska and in India .
 Jeffers, Jeffers, Massachusetts Institute of Technology, Alaska, India
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Jeffers, Jeffers, Massachusetts Institute of Technology, Alaska, India