countries. Finally, in the 1980s, Erdős was able to make contact with several relatives of Ree's with the help of Hungary's Ministry of Foreign Affairs and the country's embassy in Pyongyang, and sent Ree an envelope containing their letters, photographs, and addresses. Ree was so excited by the news that he forwarded the envelope to his mother and younger sister in South Korea, which reportedly resulted in them being investigated by South Korea's intelligence services. Ree remained banned from South Korea until 1996, when the ban was cancelled as he was invited to the 50th anniversary ceremony of the . According to his colleagues, Rimhak Ree identified his nationality as "Joseon", which is a former name of Korea as well as a current autonym of North Korea. Publications Notes References External links 1922 births 2005 deaths South Korean emigrants to Canada Korean expatriates in China Canadian mathematicians 20th-century Korean mathematicians Korean people of Manchukuo People from Hamhung Seoul National University alumni University of British Columbia alumni Academic staff of Seoul National University University of British Columbia faculty