1. Autrum H, Wiedemann I (1962) Versuche über den Strahlengang im Insektenauge. Z Naturforsch 17b:480?482
2. Cheng K, Collett TS, Wehner R (1986) Honeybees learn the colours of landmarks. J Comp Physiol A 159:69?73
3. Dartnall HJA, Bowmaker JK, Mollon JD (1983) Microspectrophotometry of human photoreceptors. In: Mollon JD, Sharpe LT (eds) Colour vision:physiology and psychophysics. Academic Press, London New York, pp 69?80 (see Fig. 1, p 72)
4. Daumer K (1956) Reizmetrische Untersuchungen des Farbensehens der Bienen. Z Vergl Physiol 38:413?478
5. De Monasterio FM, McCrae EP, Newlander JK, Schein SJ (1985) Density profile of blue-sensitive cones along the horizontal meridian of macaque retina. Invest Ophthal Visual Sci 26:289?302