Further reading Kemp, Alan C. & Woodcock, Martin (1995): The Hornbills: Bucerotiformes. Oxford University Press, Oxford, New York. Maclean, Gordon Lindsay & Roberts, Austin (1988): Roberts' Birds of Southern Africa (Revised Edition). Hyperion Books. Wallace, Alfred Russel (1863): "The Bucerotidæ, or Hornbills ". The Intellectual Observer June 1863: 309–316. Zimmerman, Dale A., Turner, Donald A., & Pearson, David J. (1999): Birds of Kenya and Northern Tanzania (Field Guide Edition). Princeton University Press.
Further reading Kemp, Alan C. & Woodcock, Martin (1995): The Hornbills: Bucerotiformes. Oxford University Press, Oxford, New York. Maclean, Gordon Lindsay & Roberts, Austin (1988): Roberts' Birds of Southern Africa (Revised Edition). Hyperion Books. Wallace, Alfred Russel (1863): "The Bucerotidæ, or Hornbills " The Intellectual Observer June 1863: 309–316. Zimmerman, Dale A., Turner, Donald A., &. Pearson, David J. (1999) Birds of Kenya and Northern Tanzania (Fie:ld Guide Edition). Princeton University Press.