1. Thornthwaite, C. W. An approach toward a rational classification of climate. Geographical review 38, 55–94 (1948).
2. Penman, H. L. Natural evaporation from open water, bare soil and grass. Proceedings of the Royal Society of London, A193, 120–146 (1948).
3. Wright, J. L. & Jensen, M. E. Peak water requirements of crops in southern Idaho. Proceedings of the American Society of Civil Engineers, Journal of the Irrigation and Drainage Division 98, 193–201 (1972).
4. Doorenbos, J. & Pruitt, W. Crop water requirements. FAO Irrig. Drain. Paper No. 24, Food and Agric. Organization, United Nations, Rome, Italy (1977).
5. Allen, R. G., Pereira, L. S., Raes, D. & Smith, M. Crop evapotranspiration-Guidelines for computing crop water requirements-FAO Irrigation and drainage paper 56. FAO, Rome 300, D05109 (1998).