1. FAO, Information on http: /faostat. fao. org/faostat/ (2012).
2. DEDE, Information on http: /www. dede. go. th/ (2012).
3. Nuri N. Mohsenin, Physical properties of plant and animal materials, second ed., Gordon and Breach Scinece, New York, (1986).
4. ASAE standard, Standards engineering practices data, forty ed., American society of agricultural engineering, USA, (1993).
5. Davies, R.M. and Zibokere, D.S., Effect of Moisture Content on Some Physical and Mechanical Properties of Three Varieties of Cowpea, Agricultural Engineering International: CIGR Journal, Manuscript No. 1700. Vol. 13, No. 1, (2011).