Norling, E. R. (1999). Perspective made easy. Dover Publications.
芝加哥风格引文Norling, Ernest R. Perspective Made Easy. Mineola, N.Y.: Dover Publications, 1999.
MLA引文Norling, Ernest R. Perspective Made Easy. Dover Publications, 1999.
警告：这些引文格式不一定是100％准确.