↑ Cassin, B. and Solomon, S. Dictionary of Eye Terminology. Gainsville, Florida: Triad Publishing Company, 1990.
↑ Malmström T, Kröger RH (2006). "Pupil shapes and lens optics in the eyes of terrestrial vertebrates". J. Exp. Biol. 209 (Bhg 1): 18–25. doi:10.1242/jeb.01959. PMID16354774. Parameter |month= tidak diketahui diabaikan (bantuan)
