1. Crop Evapotranspiration – Guidelines for Computing Crop Water Requirements FAO Irrigation and Drainage Paper 56;Allen,1998
2. Chapagain, A.K. and Hoekstra, A.Y. 2004. Water footprints of nations, Value of Water Research Report Series No. 16, UNESCO-IHE, Delft, the Netherlands.
3. Looking ahead to 2050: scenarios of alternative investment approaches;De Fraiture,2007
4. Tranfer of hexazinone and glyphosate through undisturbed soil columns in soils under Christmas tree cultivation;Doussett;Chemosphere,2004
5. EPA, 2010. National Recommended Water Quality Criteria, United States Environmental Protection Agency.