Sandberg R.L., A.J. Paul, D.A. Raymondson, S. Hädrich, D.M. Gaudiosi, J. Holtsnider, R.I. Tobey, O. Cohen, M. Murnane, H. Kapteyn, and C. Song, Physical Review Letters99, (2007).
Popmintchev T., M.E. Grisham, D.M. Gaudiosi, B.A. Reagan, O. Cohen, M.A. Berrill, M. Murnane, H. Kapteyn, and J.J. Rocca, inUnknown(IEEE, Baltimore, Md, Usa, 2007).