Boonklong, O. , Jaroensutasinee, M. , Jaroensutasinee, K. (2007). 'Computation of D8 Flow Line at Ron Phibun Area, Nakhon Si Thammarat, Thailand'. World Academy of Science, Engineering and Technology, Open Science Index 9, International Journal of Environmental and Ecological Engineering, 1(9), 103 - 106.