1. E. Union, http://www.rohs.eu/english/index.html for the RoHS regulation (2003).
2. Y. Zhang, G. Breck, F. Humiec, K. Murski, and J.A. Abys, An Alternative Surface Finish for Tin/Lead Solders: Pure Tin, SMI’96 Proceedings San Jose, CA, Sep. (1996), p. 641.
3. S. Winkler and B. Hom, A Look at the Past Reveals a Leadfree Drop-In Replacement, High Density Interconnect (HDI) on-line, http://www.hdi-online.com (2001).
4. B. Dunn, A Laboratory Study of Tin Whisker Growth (European Space Agency, STR-223, 1987), p. 1.
5. Y. Hada, O. Morikawa, and H. Togami, 26th Annual National Relay Conference (1978), p. 9.1.