Rui Tang Fengming Zhang Yong-Bin Kim Quantum-dot cellular automata SPICE macro model. 108-111 2005 conf/glvlsi/2005 ACM Great Lakes Symposium on VLSI http://doi.acm.org/10.1145/1057661.1057688 db/conf/glvlsi/glvlsi2005.html#TangZK05