B. Ayanwale, A. Lanko, and Y. Kudu, “Performance and Egg Quality Characteristics of Pullets Fed Activated Sheabutter Charcoal Based Diets”, Int. J. Poult. Sci., vol. 5, no. 10, pp. 927–931, Sep. 2006, doi: 10.3923/ijps.2006.927.931.