9Dawalibi F. Electromagnetic fields generated by overhead and buried short conductors part 2-ground networks [J]. IEEE Transactions on Power Delivery, 1986, 1(4): 112-119.
10Otero A F, Cidras J, del Alamo J L. Frequency dependent grounding system calaulation by means of a conventional nodal analysis technique[J]. IEEE Transaction on Power Delivery, 1999, 14(3): 873-878.