59644
Life and career 1960s Upon completion of his schooling at the Orthodox Seminary in Sofia , Bulgaria , he went on to study opera singing with noted Bulgarian and European pedagogues , including Stojan Kissjov and Anita Salta .
 Orthodox Seminary, Sofia, Bulgaria
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Orthodox Seminary, Sofia, Bulgaria