Powell, P. W., Wolfskill, G., & Palmer, S. H. (1981). Essays on frontiers in world history. University of Texas Press.
芝加哥风格引文Powell, Philip Wayne, George Wolfskill, 与 Stanley H. Palmer. Essays on Frontiers in World History. Austin: University of Texas Press, 1981.
MLA引文Powell, Philip Wayne, et al. Essays on Frontiers in World History. University of Texas Press, 1981.
警告：这些引文格式不一定是100％准确.