1. Akunna, J.C., C. Bizeau and R. Moletta, 1993, Nitrate and nitrite reductions with anaerobic sludge using various carbon sources: glucose, glycerol, acetic acid, lactic acid and methanol, Water Research, 27, 1303-1312
2. Bodik, I., A. Blstakova, S. Sedlacek and M. Hutnan (2009). Biodiesel waste as source of organic carbon for municipal WWTP denitrification, Bioresource Technology, 100, 2452-2456
3. Christensen, T.H., 2011, Landfilling: Leachate Treatment, Chapter 10.11 in: Christensen, T.H., Solid Waste Management and Technology, Blackwell Publishing Ltd, John Wiley & Sons, ISBN 9781405175173, 1026pp
4. Elefsiniotis, P., R. Manohanaran and D.S. Mavinic, 1989, The effects of sludge recylce ratio on nitrification-denitrification performance in biological treatment of leachate. Environmental Technology Letters, 10, 1040-1050, p.1043
5. Environment Agency (1996). A Review of the Composition of Leachates from Domestic Wastes in Landfill Sites. Report No. CWM 072/95, published by the Waste Technical Division of the Environment Agency, in the series “The Technical Aspects of Controlled Waste Management”, 550pp, August 1996