THE WORLD BOOK.. (2007). The world book W-X-Y-Z volume 21. World Book.
芝加哥风格引文THE WORLD BOOK.. The World Book W-X-Y-Z Volume 21. Chicago: World Book, 2007.
MLA引文THE WORLD BOOK.. The World Book W-X-Y-Z Volume 21. World Book, 2007.
警告：这些引文格式不一定是100％准确.