Paryad, A., and M. Rashidi. “Effect of Yeast (Saccharomyces Cerevisiae) on Apparent Digestibility and Nitrogen Retention of Tomato Pomace in Sheep”. Pakistan Journal of Nutrition, vol. 8, no. 3, Feb. 2009, pp. 273–278, https://doi.org/10.3923/pjn.2009.273.278.