1. Andow DA, Hidaka K (1989) Experimental natural history of sustainable agriculture: syndromes of production. Agric Ecosyst Environ 27:447–462
2. Asano H (2000) Effect of harvest time on protein composition (glutelin, prolamin, albumin) and amlose content in paddy rice cultivated by Aigamo duck farming system. Jpn Poult Sci 3:323–330
3. Bray F (1990) The rice economies, technology and development in Asian societies. Basil Blackwell, Oxford, 1986
4. Cao YJ (1999) Experiment of increasing rice yield by seed soaking with biogas fermentative liquid (slurry). China Biogas 4:34–35, in Chinese with English abstract
5. Castilla NP, Vera Cruz CM, Mew TW (2003) Using rice cultivar mixtures: a sustainable approach for managing diseases and increasing yield. Int Rice Res Notes 28:5–11