%0 journal article %@ 0031-9007 %A Havermeyer, F.,Rupp, R. A.,Lyuksyutov, S. F.,Eckerlebe, H.,Staron, P.,Vollbrandt, J. %D 1998 %J Physical Review Letters %N 15 %P 3272-3275 %T Nondestructive resolution of higher harmonics of light-induced volume gratings in PMMA with Cold Neutrons %U 15 %X