Rigg และผู้แต่งคนอื่นๆ. 1985. problems of agricultural intensification in a marginal rainfed environment a study of farmers'practices and government policies in two villages in northeastern ThailandJonathan D.Rigg. London:University of London;
Rigg และผู้แต่งคนอื่นๆ. (1985) problems of agricultural intensification in a marginal rainfed environment a study of farmers'practices and government policies in two villages in northeastern ThailandJonathan D.Rigg (รายงานผลงานวิจัย). University of London:London.
Rigg และผู้แต่งคนอื่นๆ. problems of agricultural intensification in a marginal rainfed environment a study of farmers'practices and government policies in two villages in northeastern ThailandJonathan D.Rigg. London:University of London, 1985.
Rigg และผู้แต่งคนอื่นๆ. (1985) problems of agricultural intensification in a marginal rainfed environment a study of farmers'practices and government policies in two villages in northeastern ThailandJonathan D.Rigg (รายงานผลงานวิจัย). University of London:London.
