Aevazi, M., and Mosaedi, A. 2012. Study the spatial pattern of rainfall in Golestan province, using geostatistical and deterministic models, Iranian Journal of Watershed Management, 26(1): 53-64. (In Persian).
Akhavan, R., Karami, M., Sousani, J. (2011). The use of two kriging and IDW on zoning and density of the forest canopy of oak coppice, Journal Forest Iran, 3(4): 305-316. (In Persian).
Afzali, S.M., and Afzali, S.A. 2013. Check the status of Shadegan wetland drought, the first conference on the protection of wetlands and aquatic ecosystems Iran, Hamedan, (In Persian).
Bonaccorso, B., Cancelliere, A., and Rossi, G. 2015. Probabilistic forecasting of drought class transitions in Sicily (Italy) using standardized precipitation index and North Atlantic oscillation index. Journal of Hydrology, 526: 136-150.
Barlow, M., Zaitchik, B., Paz, S., Black, E., Evans, J., and Hoell, A. 2016. A review of drought in the Middle East and southwest Asia. Journal of Climate, 29(23): 8547-8574.
Broghani, M., Moradi, H.R., and Zanganeh Asadi, M.A. 2015. Zoning and determine the best indicator of drought in Khorasan Razavi, Iranian Journal Studies of Arid Zones, 5(19): 70-84. (In Persian).
Cambardella C.A., Moorman T.B., Novak J.M., Parkin T.B., Karlen D.L., Turco R.F., and Koropaka A.E. Field-scale variability of soil properties in centeral Iowa soils. Soil Sci. Soc. Am. J. 58: 1501-1511.
Edwards, D.C., and McKee, T.B. 2015. Characteristics of 20th century drought in the United States at multiple time scales. Atmospheric science paper; no. 634.
Feng, S., Trnka, M., Hayes, M., and Zhang, Y. 2017. Why Do Different Drought Indices Show Distinct Future Drought Risk Outcomes in the US Great Plains? Journal of Climate, 30(1): 265-278.
Fathi, Hafashjani, A., Bygi, H., Davuodyan, A., and Tabatabaee, H. 2014. Comparison of spatial interpolation methods and select the most appropriate method for zoning nitrate and phosphate in the Shahrekord, Iranian Journal of Irrigation and Water, 4(15): 51-63. (In Persian).
Farajzadeh, M., and Ahmadian, K. 2014. Temporal and spatial analysis of drought using SPI index in Iran, Iranian Journal of natural environmental hazards, 3(4): 1-16. (In Persian).
Ghorbani, N., and Motamed Vaziry, B. 2016. Statistics on land use zoning of drought severity watershed case study Ghezelozan, National Hydrology Conference semi-arid areas, Sanandaj, Kordestan province, (In Persian).
Hao, Z., and AghaKouchak, A. (2014. A nonparametric multivariate multi-index drought monitoring framework. Journal of Hydrometeorology, 15(1): 89-101.
Kingston, D.G., Stagge, J.H., Tallaksen, L.M., and Hannah, D.M. 2015. European-scale drought: understanding connections between atmospheric circulation and meteorological drought indices. Journal of Climate, 28(2): 505-516.
Kohl, E., and Knox, J.A. 2016. My Drought is Different from Your Drought: A Case Study of the Policy Implications of Multiple Ways of Knowing Drought. Weather, Climate, and Society, 8(4): 373-388.
Khosravi, Y., and Abbasi, E. 2016. Spatial analysis of environmental data with geostatistics, Zanjan, Azarkalak.
Kuoch, Y., Hossini, S.M., Mohammadi, J., and Hojjati, S.M. 2012. Evaluation of soil spatial structure in a beech forest biomass using geostatistics, Iranian Journal of Soil and Water Sciences Agriculture, 16 (60): 239-250. (In Persian).
Mahmuodabadi, A., Sarmadian, F., and Savaghebi, G. 2013. Geostatistical study the spatial variability of soil physical and chemical properties influenced by the type of land use (case study of of Forest Park Cheetgar), Iranian Journal of Watershed Management, (100): 28-38. (In Persian).
Maroufi, S., Golmohamadi, G., Mohammadi, K., Zare, and Abyaneh, H. 2009. Evaluation of geostatistical methods to estimate the spatial distribution of precipitation in the province, GIS environment, Iranian Journal of Knowledge of soil and water, 19(2): 147-164. (in Persian).
Mozaffari, G., Mir Mousavi, H., and Khosravi, Y. 2012. Evaluation of geostatistical methods and linear regression to determine the spatial distribution of precipitation, Iranian Journal of Geography and Development, 10(27): 63-76. (in Persian).
Moradi, H.R., Fazelpor, M.R., Sadeghi, H.R. and Hossini, Z. 2008. The study of land use change on desertification using remote sensing in Ardakan area, Iranian Journal of Range and Desert Researches, 15(1): 1-12. (in Persian).
-Musuuza, J.L., Van Loon, A.F., and Teuling, A.J. 2016. Multiscale evaluation of the Standardized Precipitation Index as a groundwater drought indicator. Hydrology and Earth System Sciences, 20(3): 11-17.
Mir Mousavi, H., Mazidi, A., and Khosravi, Y. 2010. Statistics to estimate the distribution of precipitation to determine the best methods of using GIS Case Study: Isfahan Province, Iranian Journal of Geographical space, 10(30): 105-120. (In Persian).
Nabipoor, Y., and Vafahkhah, M. 2016. Three methods of geostatistics for estimation of rainfall in the catchment Haji Ghoshan, Iranian Journal of Range and Watershed, 69(2): 487-502. (In Persian).
Naserzadeh, M.H., and Ahmadi, A. 2012. Meteorological drought indices in evaluating drought performance review and Zoning in Qazvin, Iranian Journal of Applied Research Geographical Sciences, 12(27): 141-162. (in Persian).
Saraf, B., Vaezi, A., Valaee, A., and Abtahi, V. 2016. Detection of hydrological and meteorological drought in South East Ouromee Lake, Iranian Journal of natural environmental hazards, 5(10): 25-42. (In Persian).
Safar Rad, T., Faraji Sabokbar, H.A., Azizi, G., and Abbaspoor, R.A. 2013. Spatial analysis of precipitation changes in central Zagros through by geostatistical methods, Iranian Journal of Geography and Development, 11(31): 149-164. (In Persian).
Shayegh, A., and Soltani, A. 2011. Comparison meteorological drought indices in Yazd, Iranian Journal Soil and Water Sciences, 15(57): 231-249. (In Persian).
Shabani, M. 2009. Evaluating the use of geostatistical methods zoning of drought severity in Fars province, Iranian Journal of Water Resources Engineering, 2(3): 31-36. (In Persian).
Steinemann, A., Iacobellis, S.F., and Cayan, D.R. 2015. Developing and evaluating drought indicators for decision-making. Journal of Hydrometeorology, 16(4): 1793-1803.
Usofi, H., Nowhegar, A., Khosravi, Z., and Azizabadi, M. 2015. Management and zoning of drought indices using SPI and RDI (Case Study: Central Province), Iranian Journal of echo Hydrology, 2(3): 344-337. (In Persian).
World Meteorological Organization (WMO) and Global Water Partnership (GWP), 2016: Handbook of Drought Indicators and Indices (M. Svoboda and B.A. Fuchs). Integrated Drought Management Programme (IDMP), Integrated Drought Management Tools and Guidelines Series 2. Geneva