二十年危机1919-1939：国际关系研究导论：an introduction to the study of international relations an introduction to the study of international relations Exploration into historical tradition in the study of international relations Introduction to study of international regions 并列题名：Exploration into historical tradition in the study of international relations 追溯柏拉图：传播学起源概论：an introduction to the study of human communication 自由与必然：社会研究导论：an introduction to the study of society 并列题名：Distributionism theory of international relations Distributionism theory of international relations 和平与战争：国际关系理论：a theory of international relations