Siyoum, Nazareth, et al. “Bacterial Profiling of Casing Materials for White Button Mushrooms (Agaricus Bisporus) Using Denaturing Gradient Gel Electrophoresis”. South African Journal of Science, vol. 106, no. 9/10, Oct. 2010, p. 6 pages, https://sajs.co.za/article/view/10116.