Erdmann, P. (1990). Discourse and grammar: Focussing and defocussing in English. M. Niemeyer.
芝加哥风格引文Erdmann, Peter. Discourse and Grammar: Focussing and Defocussing in English. Tübingen: M. Niemeyer, 1990.
MLA引文Erdmann, Peter. Discourse and Grammar: Focussing and Defocussing in English. M. Niemeyer, 1990.
警告：这些引文格式不一定是100％准确.