Ogundipe P. A. & Tregidgo P. S. (1974). Practical English: A comprehensive secondary course. Book four. Longman.
芝加哥风格引文Ogundipe P. A. 与 Tregidgo P. S. Practical English: A Comprehensive Secondary Course. Book Four. England: Longman, 1974.
MLA引文Ogundipe P. A. 与 Tregidgo P. S. Practical English: A Comprehensive Secondary Course. Book Four. Longman, 1974.
警告：这些引文格式不一定是100％准确.