374329
In the 1921 race , the M. 19 competed against two M. 7 s , but the M. 19 had to withdrawn after the 12th lap with a fractured crankshaft which ruptured a fuel line causing the aircraft to catch fire .
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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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