Mohun, S. M., Davies, W. L., Bowmaker, J. K., Pisani, D., Himstedt, W., Gower, D. J., Hunt, D. M., Wilkinson, M.
Identification and Characterization of Visual Pigments in Caecilians (Amphibia: Gymnophiona), an Order of Limbless Vertebrates with Rudimentary Eyes (2010)
J. Exp. Biol. 213, 3586-92. doi:10.1242/jeb.045914
Warrant E.J., Nilsson D.-E. (1998) Absorption of White Light in Photoreceptors. Vision Res., Vol. 38, No. 2, pp. 195-207. PII: S0042-6989(97)00151-X
Stavenga D., Smits R.P., Hoenders B.J. (1993) Simple Exponential Functions Describing the Absorbance Bands of Visual Pigment Spectra. Vision Res. 33(8) pp. 1011-1017. doi:10.1016/0042-6989(93)90237-Q