Butler, Hennie, and Ordino Kok. 2008. “Relationship Between Group Size and Feeding Success of Cattle Egrets (Bubulcus Ibis) in the Central Free State”. Suid-Afrikaans Tydskrif Vir Natuurwetenskap En Tegnologie / <i>South African Journal of Science and Technology</I&gt; 27 (3), 216-27. https://doi.org/10.4102/satnt.v27i3.92.