1. The Principles of Pollination Ecology;Faegri,1979
2. The importance of perfume in the discovery of food by the worker honey-bee (Apis mellifera L.);Butler,1951
3. The evolutionary adaptation of flower colors and the insect pollinators' color vision;Chittka;J. Comp. Physiol. Ser. A,1992
4. Floral coloration, its colorimetric analysis and significance in anthecology;Kevan,1978
5. Floral colours through the insect eye: what they are and what they mean;Kevan,1983