12070
They also participated at the 2000 Summer Olympics , where they lost both of their matches , eliminated in the second preliminary round by Lina and Petia Yanchulova , also sisters .
 Lina, Petia Yanchulova
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Lina, Petia Yanchulova