2. Yuan Dynasty, the most extensive dynasty in the history of China.
3. Self-sufficiency and the stability of feudal economy were the fundamental reasons for the "closed door" policy in Qing Dynasty.
4. What is China17th Century Craft Encyclopedia? Who is the author? "Heavenly Creations" Song Yingxing
5. When did Tibet become an inalienable part of China Yuan Dynasty?
6. Who contributed to the contacts between the Tang Dynasty and Japan? Japan: Sent to Tang Dynasty: Jian Zhen.