Shack-Hartmann tomographic wavefront reconstruction using LGS: analysis of spot elongation and fratricide effectC. Robert, J.-M. Conan, D. Gratadour, C. Petit and T. Fusco1st AO4ELT conference - Adaptive Optics for Extremely Large Telescopes, (2010) 05010DOI: https://doi.org/10.1051/ao4elt/201005010