Cavka A., Alriksson B., Rose S.H., Van Zyl W.H., Jönsson L.J. Production of cellulosic ethanol and enzyme from waste fiber sludge using SSF, recycling of hydrolytic enzymes and yeast, and recombinant cellulase-producing Aspergillus niger. 2014. Journal of Industrial Microbiology and Biotechnology. 41. 8. 1191-1200. 10.1007/s10295-014-1457-9.