A. Gandomkar and  R. Dehghani,  Studying the Trend of Drought in Fars Province (Iran) using SPI Method.   journal   = {International Journal of Environmental and Ecological Engineering}, [online]. World Academy of Science, Engineering and Technology.
    April 2012, vol. 64(4). 228 - 230
    [viewed 25 April 2024]. Available from: https://publications.waset.org/pdf/14269.