Sŭng-myŏng Yi

• Chŏng Kwajŏng ŭi chonghapchŏk sae yŏnʼgu
• Kugŏ ŏhwi ŭi ŭimi kujo e taehan yŏnʼgu
• Simni ŏnŏhak
• Ŭimiron yŏnʾgu ŭi sae panghyang