188031
It came in four port ratios : 8 , 9/12 , 8/12 , and 10/12 , which sounds very much like a Biersach and Niedermeyer Co. . Mobil Directo , an early version of the Allertor , and in fact , the 9/12 and 10/12 rotors were derived from Federal Signal .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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