Research on the theory and system of taxpayer's rights protection 并列题名:Research on the theory and system of taxpayer's rights protection Research on the theory and system of ecological civilization Research on the legal system of cultivated land protection 并列题名:Research on the theory and system of ecological civilization Research on the international legal system of diplomatic protection research on the modern and contemporary Chinese lyric fictions research on the sex ratio at birth of the minority population research on the theory and practice