说明：  《电力系统状态估计》于尔铿 电科院于尔铿老师的《电力系统状态估计》一书是电力系统状态估计的经典著作，但因为是专业书籍，年代也比较早，一般的书店很难有卖- -!!
(" Power System State Estimation" in Erkeng EPRI in Erkeng teacher' s " power system state estimation," a book is a classic power system state estimation, but because it is professional books,' s relatively early, in general bookstores difficult have to sell-!!)