http://www.directoryofeducation.net/colleges_universities/byCountry/Indonesia/University+of+North+Sumatra/6081/

http://www.directoryofeducation.net/colleges_universities/byCountry/Indonesia/University+of+North+Sumatra/6081/

http://www.directoryofeducation.net/colleges_universities/byCountry/Indonesia/University+of+North+Sumatra/6081/

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