Thomson, A. (1966). A practical english grammar exercises-4 Vol 4. O.U.P.
芝加哥风格引文Thomson, A. A Practical English Grammar Exercises-4 Vol 4. London: O.U.P, 1966.
MLA引文Thomson, A. A Practical English Grammar Exercises-4 Vol 4. O.U.P, 1966.
警告：这些引文格式不一定是100％准确.