213606
1st Reserve Army 2nd Reserve Army 3rd Reserve Army 4th Reserve Army 5th Reserve Army 6th Reserve Army 7th Reserve Army Formed on 28 May 1942 in the STAVKA Reserves .
 6th
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 6th