1. Standard methods for the examination of water and wastewater;Anon,1975
2. Soil survey—laboratory methods and procedures for collecting soil samples;Anon,1972
3. Biogas production from crops and organic wastes;Badger;New Zealand Journal of Science,1979
4. The anaerobic fermentation of lignin;Boruff;American Chemical Society Journal,1934
5. The economics of SNG production by anaerobic digester of specially grown plant matter;Fraser,1977