1. AFMIS, 2011. Commodity profile of corn region I. Agriculture and fisheries market information system, online available at http://afmis.da.gov.ph/.
2. Effect of calcium on the response of a field-grown rice plant to water stress;Biswas;Proc. Indian Natl. Sci. Acad.,1982
3. The effect of toposequence position on soil properties. hydrology, and yield of rainfed lowland rice in Southeast Asia;Boling;Field Crops Res.,2008
4. Nitrogen – total;Bremner,1996
5. Changes in paddy soils under transition to water-saving and diversified cropping systems;Buresh,2010