Gill, Frank B.; Slikas, Beth; Sheldon, Frederick H. (2005). "Phylogeny of titmice (Paridae): II. Species relationships based on sequences of the mitochondrial cytochrome-b gene". Auk. 122: 121–143. doi:10.1642/0004-8038(2005)122[0121:POTPIS]2.0.CO;2.
Lambert, Frank (1989). "Fig-Eating by Birds in a Malaysian Lowland Rain Forest". Journal of Tropical Ecology. 5 (4): 401–412. doi:10.1017/s0266467400003850.