%0 Journal Article %A E. Ya. Komarov %A I. B. Borovskii %T Spectra of threshold potentials of rare-earth elements of the lanthanoid group %J Doklady Akademii Nauk %D 1975 %P 288-289 %V 225 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/item/DAN_1975_225_2_a11/ %G ru %F DAN_1975_225_2_a11