Hall, R., and J. D. Holloway (editors). 1998. Biogeography and geological evolution of SE Asia. Leiden: Backhuys Publishers. pp 417.
Dickinson, E. C., R. S. Kennedy, and K. C. Parkes. 1991. The birds of the Philippines: an annotated check-list. British Ornithologists' Union (Checklist no. 12). Tring, UK.