Sanan Peukrai. 1990. Upland rice cultivation practices for sustainable production on the steep land. Graduate School, Chiang Mai University;
Sanan Peukrai. (1990) Upland rice cultivation practices for sustainable production on the steep land . Chiang Mai University/Chiang Mai.
Sanan Peukrai. Upland rice cultivation practices for sustainable production on the steep land. . Chiang Mai:Chiang Mai University, 1990.
Sanan Peukrai. (1990) Upland rice cultivation practices for sustainable production on the steep land . Chiang Mai University/Chiang Mai.