1. Standard Methods for the Examination of Water and Wastewater;APHA,1998
2. Seasonal variability of hydraulic conductivity;Asare;Trans. ASAE,1993
3. Investigating seal formation from manure infiltration into soils;Barrington;Trans. ASAE,1989
4. The sealing of soils by manures;Barrington;Can. Agric. Eng.,1987
5. Attenuation of Nitrate in the Sub-surface Environment;Buss,2005