In 1962, Kim Bong-han, a Professor of Pyongyang Medical University, reported that he had found the anatomical structure of meridian-collaterals, which he named Bonghan corpuscles (BHCs) and Bonghan ducts (BHDs).
Pada 1962, Kim Bong-han, seorang Professor dari Universitas Kedokteran Pyongyang, melaporkan bahwa dia telah menemukan struktur anatomi dari kolateral meridian, yang dinamakannya "Bonghan corpuscles" (BHCs) dan "Bonghan ducts" (BHDs).