WebMD. https://www.webmd.com/eye-health/what-you-need-to-know-about-color-blindness-tests#1
Diakses pada 25 Maret 2019All About Vision. https://www.allaboutvision.com/eye-exam/color-blind-tests.htm
Diakses pada 25 Maret 2019American Academy of Ophthalmology. https://www.aao.org/eye-health/diseases/how-color-blindness-is-tested
Diakses pada 25 Maret 2019Colour Blind Awareness. http://www.colourblindawareness.org/colour-blindness/diagnosis/
Diakses pada 25 Maret 2019