1. Opec F.F.I.D. (2018) Wastewater Report 2018: The Reuse Opportunity.International Water Association: IWA.https://www.iwa-network.org/wp-content/uploads/2018/02/OFID-Wastewater-report-2018.pdf
2. Overview of legislation on sewage sludge management in developed countries worldwide
3. Bień J.B.andWystalska K.(2002).Osady ściekowe. TeoriaI Praktyka Wyd. Politechniki Częstochowskiej Częstochowa.
4. Enhancing Anaerobic Fermentation of Sewage Sludge for Increasing Biogas Generation