The following manuscript have been forgotten to mention in the reference list. J. Cryst. Growth 291(2006) 309–313 After the sentence in the page 1649 at the first paragraph of “3.4. Optical properties of Pr: GYbF”  should be added as following. Absorption and infrared emission spectra of both undoped and Pr3+-doped Gd1 xYbxF3 were recorded under excitation on the broad band absorption of Yb3+ at 935.5 nm . In the reference list,  should be added as following.  Rayko Simura, Anis Jouini, Kei Kamada, Akira Yoshikawa, Kenji Aoki, Yannick Guyot, Georges Boulon, Tsuguo Fukuda, J. Cryst. Growth 291(2006) 309–313. The authors and the Publisher regret the error that appeared in their paper.