Ollerton, Jeff, and Clive Nuttman. “Aggressive Displacement of Xylocopa Nigrita Carpenter Bees from Flowers of Lagenaria Sphaerica (Cucurbitaceae) by Territorial Male Eastern Olive Sunbirds (Cyanomitra Olivacea) in Tanzania”. Journal of Pollination Ecology 11 (May 15, 2013): 21–26. Accessed February 7, 2023. https://pollinationecology.org/index.php/jpe/article/view/205.