The following reference works are cited in this example problem:
Liu, H., Yu, C., Li, P., & Chen, J. (2008). Current Crowding and its Effects on Electromigration and Interfacial Reaction in Lead-Free Solder Joints. Journal of Electronic Packaging. 130: 59-63.
Wang, S. & Liang, L. (2007). Solder joint reliability under electromigration and thermal-mechanical load. Proc. IEEE Electronic Components and Technology Conference (ECTC 07). 1074-1083.
Chao, B.,Chae, S. H., Zhang, X., Lu, K. H., Im, J., & Ho, P. S. (2007). Investigation of diffusion and electromigration parameters for Cu-Sn intermetallic compounds in Pb-free solders using simulated annealing. Acta Mater.55:2805-2814.