291785
Three horse have won the Chairman 's – SA Derby double : Markham ( 1997 ) , Mummify ( 2003 ) , Rebel Raider ( 2009 ) Race name Race distance Race grade Race venue The winners See also References
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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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