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They are considered as the most successful , commercially , group in the history of Greek discography with three gold and five platinum albums ( among which : Yia Tous Prigkipes Tis Dytikis Ohthis , Stilvi , Yparhoun Hrysopsara Edo ? ) .
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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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