30.

A. Ellens, K. Krämer, and H.U. Güdel
Comparison of the electron-phonon coupling strength of U³⁺ and Nd³⁺ in K2LaCl5
J. Lumin. 76 - 77 (1998) 548 – 550.

31.

K.W. Krämer, H.U. Güdel, and R.N. Schwartz
NIR to VIS upconversion in LaCl3 : 1% Er³⁺. One- and two-color excitations around 1000 and 800 nm
J. Alloys Comp. 275 – 277 (1998) 191 – 195.

32.

W. Henggeler, N. Cavadini, A. Furrer, H.U. Güdel, K. Krämer, and H. Mutka
Magnetic excitations in the quantum spin system KCuCl3
ILL annual report 1998, 22 - 23.