Koller, E. L. (1915). Pictorial perspective, prepared specially for home study. International Correspondence Schools.
Chicago-referens (17:e uppl.)Koller, Edmund Leonard. Pictorial Perspective, Prepared Specially for Home Study. Scranton, Pa: International Correspondence Schools, 1915.
MLA-referens (9:e uppl.)Koller, Edmund Leonard. Pictorial Perspective, Prepared Specially for Home Study. International Correspondence Schools, 1915.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.