Focusing effect in X-ray diffraction imaging of LiNbO3 crystals under static electric field P. Pernot-Rejmánková, W. Laprus and J. Baruchel Eur. Phys. J. AP, 8 3 (1999) 225-232 Published online: 15 December 1999 DOI: 10.1051/epjap:1999249