Norling, E. R. (1999). Perspective made easy. Dover Publications.
Chicagoスタイル(17版)引用形式Norling, Ernest R. Perspective Made Easy. Mineola, N.Y.: Dover Publications, 1999.
MLA(9版)引用形式Norling, Ernest R. Perspective Made Easy. Dover Publications, 1999.
警告: この引用は必ずしも正確ではありません.