Reference

Wenjuan Wang, Chuanyin Dai, Per Alström, Chunlan Zhang, Yanhua Qu, Shou-Hsien Li, Xiaojun Yang, Na Zhao, Gang Song, Fumin Lei (2014): Past hybridization between two East Asian long-tailed tits (Aegithalos bonvaloti and A. fuliginosus) – Frontiers in Zoology – 2014: 0001-40-0013.