@article{DAN_1971_198_6_a14,
     author = {N. K. Bel'skii and D. A. Muhamedova},
     title = {Experimental determination of inverse population in the crystal $\mathrm{CaWO}_4:\mathrm{Nd}^{3+}$},
     journal = {Doklady Akademii Nauk},
     pages = {1303--1305},
     publisher = {mathdoc},
     volume = {198},
     number = {6},
     year = {1971},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1971_198_6_a14/}
}