1. A Penman for all Seasons;Allen;J. Irrig. Drain. Eng. ASCE,1986
2. Allen R.G. 1993. Evaluation of a temperature difference method for computing grass reference evapotranspiration. Report submitted to the Water Resources Development and Man Service, Land and Water Development Division, FAO, Rome. 49 pp.
3. Allen, R.G., 1995. Evaluation of procedure for estimating mean monthly solar radiation from air temperature. Report, United Nations Food and Agricultural Organization (FAO), Rome.
4. Assessing integrity of weather data for reference evapotranspiration estimation;Allen;J. Irrig. Drain. Eng. ASCE,1996
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 no. 56, Rome.