Structural, down- and phase selective up-conversion emission properties of mixed valent Pr doped into oxides with tetravalent cations

C. Tiseanu, V. Parvulescu, D. Avram, B. Cojocaru, N. Apostol, A. V. Vela-Gonzalez,   M. Sanchez-Dominguez, Phys. Chem. Chem. Phys. 16, 5793 (2014).