1. Allan, J.A., 1997 Virtual water: a long term solution for water short Middle Eastern economies? Occasional Paper 3, School of Oriental and African Studies (SOAS), University of London.
2. The Middle East Water Question;Allan,2001
3. An update for the definition of reference evapotranspiration;Allen;ICID Bulletin,1994
4. An update for the calculation of reference evapotranspiration;Allen;ICID Bulletin,1994
5. Allen, R.G., Pereira, L.S., Raes, D., Smith, M., 1998. Crop evapotranspiration: guidelines for computing crop water requirements. FAO Irrigation and Drainage Paper 56, FAO, Rome, Italy.