New phase of cluster-based economic development in western countries 并列题名：New phase of cluster-based economic development in western countries A study of trade & economic development of the Gulf countries 并列题名：A study of trade & economic development of the Gulf countries Theory of economic development of large countries Research on the quality of economic development in western ethnic areas 并列题名：Research on the quality of economic development in western ethnic areas 并列题名：Theory of economic development of large countries The Chinese medicine development in foreign countries 并列题名：The Chinese medicine development in foreign countries