Brepols, C., Dorgeloh, E., Frechen, F. B., Fuchs, W., Haider, S., Joss, A., … Wozniak, T. (2008). Upgrading and retrofitting of municipal wastewater treatment plants by means of membrane bioreactor (MBR) technology. Desalination, 231(1–3), 20-26. https://doi.org/10.1016/j.desal.2007.11.035