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A combined arms operation , Brochet involved 18 battalions of French and South Vietnam ese troops and 42nd and 50th Viet Minh Regiments , fighting in the southern reaches of the Red River Delta near Tonkin in North Vietnam .
 South Vietnam, Viet Minh, Red River Delta, Vietnam
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 South Vietnam, Viet Minh, Red River Delta, Vietnam