Mohammed A. El-Shirbeny, and Bassam Abdellatif. “REFERENCE EVAPOTRANSPIRATION BORDERS MAPS OF EGYPT BASED ON KRIGING SPATIAL STATISTICS METHOD”. GEOMATE Journal, vol. 13, no. 37, Mar. 2017, pp. 1-8, https://geomatejournal.com/geomate/article/view/1496.