Spatially calibrated elemental depth profiling using LIPS and 3D digital microscopy S. Siano, I. Cacciari, A. Mencaglia and J. Agresti Eur. Phys. J. Plus, 126 12 (2011) 120 Published online: 12 December 2011 DOI: 10.1140/epjp/i2011-11120-y