瀬木碧 [Midori Segi] (2001). 北朝鮮を知りすぎた医者国境からの報告 [The doctor who knew too much about North Korea: A report from inside the borders]. 草思社 [Sōshisha]. ISBN4-7942-1090-6. OCLC48952380. JPNO20208614.
Koehler, Robert (25 September 2006). "Things Getting Darker for Vollertson". The Marmot's Hole. Archived from the original on 27 September 2007. Retrieved 9 July 2007.
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Vollertson, Norbert (2004). Inside North Korea: Diary of a Mad Place. San Francisco: Encounter Books. ISBN1-893554-87-2. OCLC226117315.
瀬木碧 [Midori Segi] (2001). 北朝鮮を知りすぎた医者国境からの報告 [The doctor who knew too much about North Korea: A report from inside the borders]. 草思社 [Sōshisha]. ISBN4-7942-1090-6. OCLC48952380. JPNO20208614.