F. Druon, S. Ricaud, D. N. Papadopoulos, A. Pellegrina, P. Camy et al., On Yb:CaF_2 and Yb:SrF_2: review of spectroscopic and thermal properties and their impact on femtosecond and high power laser performance [Invited], Optical Materials Express, vol.1, issue.3, pp.489-502, 2011.
DOI : 10.1364/OME.1.000489

A. Lyberis, G. Patriarche, P. Gredin, D. Vivien, and M. Mortier, Origin of light scattering in ytterbium doped calcium fluoride transparent ceramic for high power lasers, Journal of the European Ceramic Society, vol.31, issue.9, p.1619, 2011.
DOI : 10.1016/j.jeurceramsoc.2011.02.038