Uniaxial stress effect on the 1A1 → 1T 1 transition of Co3+ in α-Al2O 3 E. Duval, R. Louat, B. Champagnon, R. Lacroix et J. Weber J. Phys. France, 36 6 (1975) 559-569 DOI: 10.1051/jphys:01975003606055900