Yang Yi Peng Li Vivek Sarin Weiping Shi Impedance extraction for 3-D structures with multiple dielectrics using preconditioned boundary element method. 7-10 2007 conf/iccad/2007 ICCAD http://doi.acm.org/10.1145/1326073.1326076 db/conf/iccad/iccad2007.html#YiLSS07