EYSHI REZAEI, E., MOHAMMADIAN, A., KOOHI, M. and BANNAYAN, M. 2011. Comparative Analysis of Drought Indices for Drought Zone Scheme of Northern Khorasan Province of Iran. Notulae Scientia Biologicae. 3, 3 (Aug. 2011), 62–69. DOI:https://doi.org/10.15835/nsb336170.