Library of Congress – Federal Research Division (2007). "Country Profile: North Korea"(PDF). Library of Congress – Federal Research Division. मूल से 26 फ़रवरी 2005 को पुरालेखित(PDF). अभिगमन तिथि 6 September 2010.
Library of Congress – Federal Research Division (2007). "Country Profile: North Korea"(PDF). Library of Congress – Federal Research Division. मूल से 26 फ़रवरी 2005 को पुरालेखित(PDF). अभिगमन तिथि 6 September 2010.