Observation of the characteristics of Tm2+ and Tm3+ in homogeneous and inhomogeneous TmSe G. Chouteau, F. Holtzberg, O. Peña, T. Penney et R. TournierJ. Phys. Colloques, 40 C5 (1979) C5-361-C5-363DOI: https://doi.org/10.1051/jphyscol:19795128