Eckstein, W. Surface Science (OP), Max Planck Institute for Plasma Physics, Max Planck Society;
Eckstein, W. (2000). Oscillations of the Sputtering Yield. Nuclear Instruments and Methods in Physics Research B, 171, 435-442. Retrieved from http://www.sciencedirect.com/science?_ob=MImg&_imagekey=B6TJN-41SCCR0-3-1S&_cdi=5315&_user=100196&_orig=browse&_coverDate=12%2F31%2F2000&_sk=998289995&view=c&wchp=dGLbVtz-zSkWz&md5=6b84003bfbc3926021eb6c96b8baf03b&ie=/sdarticle.pdf.