APA-referens (7:e uppl.)

Norling, E. R. (1999). Perspective made easy. Dover Publications.

Chicago-referens (17:e uppl.)

Norling, Ernest R. Perspective Made Easy. Mineola, N.Y.: Dover Publications, 1999.

MLA-referens (9:e uppl.)

Norling, Ernest R. Perspective Made Easy. Dover Publications, 1999.