Eneji, C.A., et al. “Effect of Refrigeration and Frozen Storage on the Shelf-Life of Beef Purchased from Local Markets and Abattoir in Calabar Metropolis-Nigeria”. Pakistan Journal of Nutrition, vol. 6, no. 6, Oct. 2007, pp. 576–581, https://doi.org/10.3923/pjn.2007.576.581.