9Wang X, DI et al. The lniluence ot Using blogas Digesters on Family Energy Consumption and Its Economic Benefit in Rural Areas--Comparative Study Between Lian- shui and Guichi in China[J]. Renewable and Sustainable En- ergyReviews, 2007, (05).
10Bbattaeharya S. C. S. Abdul Pet al. Emissions from Biomass Energy Use in Some Selected Asian Countries [J]. Energy, 2000, (02).