Perkins, R. L., & Kierkegaard, S. (1985). The concept of anxiety. International Kierkegaard commentary.
芝加哥风格引文Perkins, Robert L., 与 Søren Kierkegaard. "The Concept of Anxiety." International Kierkegaard Commentary 1985.
MLA引文Perkins, Robert L., 与 Søren Kierkegaard. "The Concept of Anxiety." International Kierkegaard Commentary, 1985.
警告：这些引文格式不一定是100％准确.