58398
Nebula s circulation was international , with only a quarter of the sales in the United Kingdom ( UK ) ; this led to disaster when South Africa and Australia imposed import controls on foreign periodicals at the end of the 1950s .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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