163534
2007 AZL Żelazny mid-air collision On 1 September 2007 , three Zlin Z-526 aircraft from the AZL Żelazny aerobatics team were performing their display .
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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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