Wertz, Daniel; Oh, JJ; Kim, Insung. The DPRK Diplomatic Relations(PDF) (报告). National Committee on North Korea: 3. 2015 [2019-11-17]. (原始内容存档(PDF)于2016-12-28).
web.archive.org
Wertz, Daniel; Oh, JJ; Kim, Insung. The DPRK Diplomatic Relations(PDF) (报告). National Committee on North Korea: 3. 2015 [2019-11-17]. (原始内容存档(PDF)于2016-12-28).