1. Addis Ababa City Administration AACA (2010) Overview Addis Ababa City Solid Waste Management System, Addis Ababa, Ethiopia. http://www.addisababacity.gov.et
2. Addis Ababa City Housing Agency AACHA (2006) Draft Report on Addis Ababa Condominium Program, Addis Ababa, Ethiopia
3. Amirhossein M, Noor E, Sharom M (2004) Anaerobic co-digestion of Kitchen Waste and Sewage Sludge for producing Biogas. In: Second International Conference on Environmental Management. Bangi (13–14 September)
4. APHA (1999) Standard methods for examinations of water and wastewater, 20th edn. American Public Health Association, Washington, DC
5. Appels L, Baeyens J, Degre`ve J, Dewil R (2008) Principles and potential of the anaerobic digestion of waste-activated sludge. Prog Energ Combust Sci 34:755–781