They involves issues related to ascertaining the history of Ancient Korea, Koguryo, Koryo and Ri Dynasty, as well as research findings in recent years, backed by a wealth of historical materials.

Among the twenty new books are "History of Korean Political System", "History of the Korean People's Anti-Aggression Struggle", "History of Korean Peasants' Uprisings" "History of Development of Korean Towns in Middle Ages", "History of Korean Mining Industry", "History of Korean Fisheries", "History of Korean Music" and "History of Korean Customs".

"History of Korean Political System" deals with Korea's political structures and its features, functions and styles ranging from the ancient times to the modern times and "History of the Korean People's Anti-Aggression Struggle" introduces their struggle against invaders in a comprehensive, scientific and theoretical way.

"History of Early Relations between Korea and Japan" (three volumes) cites old documents, archaeological evidences and names of some places to prove that Koreans began migrating to islands of Japan and settling down there in B.C. fourth-B.C. third centuries and formed minor countries.

Jo Hui Sung, director of the History Institute of the Academy of Social Science and one of the compilers, told KCNA that the books would be much helpful to the readers in getting a correct understanding of the

5 000-year-old history and brilliant culture of the Korean nation.