The paper provides a good technical overview over the attached growth and sludge blanket process in anaerobic wastewater treatment.
VIGNESWARAN, S. BALASURIYA, B. L. N. VIRARAGHAVAN, T. (1986): Environmental Sanitation Reviews. Anaerobic Wastewater Treatment – Attached Growth and Sludge Blanket Process. Bangkok: Environmental Sanitation Information Center (ENSIC)