TY - JOUR A1 - Um, M.-J. A1 - Kim, Y. A1 - Park, D. A1 - Kim, J. T1 - Effects of different reference periods on drought index (SPEI) estimations from 1901 to 2014 JO - Hydrol. Earth Syst. Sci. J1 - HESS VL - 21 IS - 10 SP - 4989 EP - 5007 Y1 - 2017/10/06 PB - Copernicus Publications SN - 1607-7938 UR - https://hess.copernicus.org/articles/21/4989/2017/ L1 - https://hess.copernicus.org/articles/21/4989/2017/hess-21-4989-2017.pdf DO - 10.5194/hess-21-4989-2017 ER -