1. Improvement of biodegradation of excess activated sludge by the high pressure;Yamazaki;J. Water and Waste in Japan,1995
2. M. Tanaka, Outline of water management, Japan Environmental Measurement and Analysis Associate, Tokyo, 1998 (Chapter 2).
3. Extraction of single-cell protein from activated sewage sludge: thermal solubilization of protein;Shier;Bioresource Technol.,1994
4. Chemical solubilization of particulate organics as a pretreatment approach;Mukherjee;Water Sci. Technol.,1992
5. The ultrasonic treatment of excess sludge as the pretreatment method about the anaerobic digestion process;Shimizu;J. Water and Waste in Japan,1992