Eloff, R.(University of Pretoria. Faculty of Engineering, Built Environment and Information Technology. Dept. of Industrial and Systems Engineering, 2011)
Mahlaba, Jabulani S.; Kearsley, Elsabe P.; Kruger, Richard A.(University of Kentucky Center for Applied Energy Research and the American Coal Ash Association, 2012)
De Beer, Darren(University of Pretoria. Faculty of Engineering, Built Environment and Information Technology. Dept. of Industrial and Systems Engineering, 2017)
Unknown author(University of Pretoria. Faculty of Engineering, Built Environment and Information Technology. Dept. of Industrial and Systems Engineering, 2011)