Study on the system of civil code China study on the system of concealment in ancient China Study on the system of energy supply in China Study on the size of civil servants in China study on history of crops in China 并列题名:Study on the system of energy supply in China Study on the legal system of mineral resources in modern China On the security law system of the civil code of China Study on codifaction of civil code in contemporary China New study on the systematization of criminal coercive measures in China