1. Abrahamson, E.W., Fager, R.S., Mason, W.T.: Comparative properties of vertebrate and invertebrate photoreceptors. Exp. Eye Res. 18, 51–67 (1974).
2. Abrahamson, E.W., Wiesenfeld, J.R.: The structure, spectra and reactivity of visual pigments. In: Handbook of Sensory Physiology (H.J.A. Dartnall, ed.), vol.VII/1, p. 69–121. Berlin-Heidelberg-New York: Springer 1972.
3. Arey, L.B.: Changes in the rod-visual cells of the frog due to the action of light. J. comp. Neurol. 26, 429–442 (1916).
4. Bäck, I., Donner, K.O., Reuter, T.: The screening effect of the pigment epithelium on the retinal rods in the frog. Vision Res. 5, 101–111 (1965).
5. Bäckström, A.-C., Donner, K.O., Hemilä, S.: The effect of Ca-ions on the kinetics of rhodopsin photoproduct decay in the living, isolated frog retina. Physica norv. 7, 177–179 (1974).