1. The origin and early history of the Mules operation
2. 2. D. Counsell Cost-benefit analysis of the Mules operation in the Australian sheep flock. Review for the Australian Wool Research and Promotion Organisation, October2000 .
3. 3. The Mackinnon Project., 2005 . Report on likely increased prevalence of breech strike and increased mortalities from flystrike if sheep were not mulesed. Report to Australian Wool Innovation, 2005.