McCombs, D. (2000). Ultima thule. Yale University Press.
芝加哥风格引文McCombs, Davis. Ultima Thule. New Haven: Yale University Press, 2000.
MLA引文McCombs, Davis. Ultima Thule. Yale University Press, 2000.
警告：这些引文格式不一定是100％准确.
APA引文