Attributes / relations provided by
♦ ¹Krebs, J. R., & Avery, M. I. (1985). Central place foraging in the European bee-eater, Merops apiaster. The Journal of Animal Ecology, 459-472.
♦ ²del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona.