Azizi, G. 2004. Releationship of Last Drought and Ground Water Resource in Qazvin Plain. Geographical Research. 46, 131-143.
Ekrami, M., M. R. Ekhtesasi., and H. Malekinezhad. 2013a. The Effects and Consequences of Climatic Drought on Time Delay and the Change in Water Discharge of Springs and Qanats(Yazd-Ardakan Plain). Iranian-Water Resources Research. 9 (2), 19-26.
Ekrami, M., H. Malekinezhad., and M. R. Ekhtesasi. 2013b. Evaluation of Meteorological drout and Hydrological Drought Impacts on Ground Water Resource. Iran-Watershed Management Scince & Engineering. 7 (20).
Hayes, M. J., M. D. Svoboda, D. A. Wilhite., and O. V. Vanyarkho. 1999. Monitoring the 1996 drought using the standardized precipitation index. Bulletin of the American Meteorological Society. 80 (3), 429-438.
Hoseinzade, M. M., A. Nohegar., and 2011. Effects of Last Two-decade on Ground Water Resource of Minab Plain and Subsidence Occurenss. Environmental Erosion. 9 (1), 75-97.
Khan, S., H. F. Gabriel., and T. Rana. 2008. Standard precipitation index to track drought and assess impact of rainfall on watertables in irrigation areas. Irrigation & Drainage Systems. 22 (2), 159-177.
Lloyd‐Hughes, B., and M. A. Saunders. 2002. A drought climatology for Europe. International Journal of climatology. 22 (13), 1571-1592.
McKee, T. B., N. J. Doesken., and J. Kleist. 1993. The relationship of drought frequency and duration to time scales. Paper read at Proceedings of the 8th Conference on Applied Climatology.
Mendicino, G., A. Senatore., and P. Versace. 2008. A Groundwater Resource Index (GRI) for drought monitoring and forecasting in a Mediterranean climate. Journal of Hydrology. 357 (3), 282-302.
Naderianfar, M., and H. Ansari. 2011. Effects of Drought Rate-Duration in Multi-Time Scale on Ground Water Levels Change (Neyshabor Plain). Water Resource Engineering. (4), 1-15.
Naderianfar, M., H. Ansari, A. Ziaie., and K. Davari. 2010. Evaluating the Ground Water Level Fluctuations under Different Climatic Condition in the Basin Neyshabour. Irrigation & Water Engineering. (3), 21-37
Shemshaki, A., Y. Mohammadi., and M. J. Bolourchi. spring2011. Investigation on Confined Aquifer & its Role on Subsidence Occurrence in Hashtgerd Plain. Scientific Quarterly Journal, GEOSCIENCES. 20 (79), 137-142.
Vicente-Serrano, S. M., and J. I. López-Moreno. 2005. Hydrological response to different time scales of climatological drought: an evaluation of the Standardized Precipitation Index in a mountainous Mediterranean basin. Hydrology and Earth System Sciences Discussions. 9 (5), 523-533.
Wilhite, D. A., and M. H. Glantz. 1985. Understanding: the drought phenomenon: the role of definitions. Water international. 10 (3), 111-120.