Heo Jun
After this, many books on medical specialties were published. There are three physicians from the Joseon Dynasty (1392-1910) who are generally credited with further development of traditional Korean medicine—Heo Jun, Saam, and Lee Je-ma. After the Japanese invasion in 1592, "Dongeui Bogam" (동의보감) was written by Heo Jun, the first of the major physicians. This work further integrated the Korean and Chinese medicine of its time and was influential to Chinese, Japanese and Vietnamese medicine.