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They were among the most popular Serbian and Yugoslav clubs , and they were nicknamed as " Crveni " ( The Reds ) because of their red shirts , in opposition to their greatest rivals BSK , who wore blue and were known as " Plavi " ( The Blues ) .
 organization: Yugoslav; organization: BSK
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
 Entities: Yugoslav, BSK 
Answer:
 organization: Yugoslav; organization: BSK