Barber, M. (2004). Two cities: Medieval Europe, 1050-1320 (2nd ed.). Routledge.
芝加哥风格引文Barber, Malcolm. Two Cities: Medieval Europe, 1050-1320. 2nd ed. London ; New York: Routledge, 2004.
MLA引文Barber, Malcolm. Two Cities: Medieval Europe, 1050-1320. 2nd ed. Routledge, 2004.
警告：这些引文格式不一定是100％准确.