89007
After D-Day , engaged chiefly in escorting bombers to oil refineries , marshalling yards , and other targets in such cities as Ludwigshafen , Stuttgart , Frankfurt , Berlin , Merseburg , and Brux .
 Ludwigshafen, Stuttgart, Frankfurt, Merseburg
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Ludwigshafen, Stuttgart, Frankfurt, Merseburg