Nam-Pukhan kwallyŏn Hŏnggari wa Pulgaria ŭi oegyo munsŏ Tong Yurŏp i kirok han haebang chŏnhu ŭi Hanbando, 1945-1956 - I, Hui og 1942-; Kim, Po-guk (Sŏnggyun'gwan Taehakkyo 'Haebang chŏnhu Han'guk munje e taehan kukchejŏk nonŭi' yŏn'gu ch'ongsŏ, 2019)