You might additionally want ...
Published by S. I., IQC GmbH
You might additionally want to consider these:
http://www.ipcc-nggip.iges.or.jp/public/gp/bgp/5_2_CH4_N2O_Waste_Water.pdf
http://www.scielo.br/pdf/sa/v72n2/0103-9016-sa-72-2-0147.pdf
HTH
Published by S. I., IQC GmbH
You might additionally want to consider these:
http://www.ipcc-nggip.iges.or.jp/public/gp/bgp/5_2_CH4_N2O_Waste_Water.pdf
http://www.scielo.br/pdf/sa/v72n2/0103-9016-sa-72-2-0147.pdf
HTH