18983
Until then , the designation had been used exclusively to identify the adjacent region of contemporary northwestern Iran , while the area of the Azerbaijan Democratic Republic was formerly referred to as " Arran " and " Shirvan " .
 Iran, Azerbaijan Democratic Republic, Arran, Shirvan
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Iran, Azerbaijan Democratic Republic, Arran, Shirvan