TY - JOURNAL OF NATURAL RESOURCES A1 - LI Ji, LI Yi, SONG Song-bai, CUI Chen-feng T1 - Multivariate Joint Distributions of Drought Variables Based on Copulas Function Y1 - 2013-01-30 16:42:00.023 JF - JOURNAL OF NATURAL RESOURCES JO - JOURNAL OF NATURAL RESOURCES SP - 312 EP - 320 VL - 28 IS - 2 UR - {https://www.jnr.ac.cn/EN/10.11849/zrzyxb.2013.02.012} N1 - 10.11849/zrzyxb.2013.02.012 ER -