Barnes, R., Filer, D., & Milton, S. (1996). Acacia karroo: Monograph and annotated bibliography. Oxford Forestry Institute, University of Oxford.

Barnes, R., D. Filer, and S. Milton. Acacia Karroo: Monograph and Annotated Bibliography. Oxford Forestry Institute, University of Oxford, 1996.

Barnes, R., et al. Acacia Karroo: Monograph and Annotated Bibliography. Oxford Forestry Institute, University of Oxford, 1996.