Keller, C. (2000). Understanding MA27 - A Numerical Example. Unspecified.
芝加哥风格引文Keller, C. Understanding MA27 - A Numerical Example. Unspecified, 2000.
MLA引文Keller, C. Understanding MA27 - A Numerical Example. Unspecified, 2000.
警告：这些引文格式不一定是100％准确.