@article{PismaZhETF.7.382,
    title = {Excitation of Forbidden and Allowed Radiative Transitions in a $CaF_2$:$Dy^{2+}$ Crystal in a Magnetic Field},
    author = {Zakharchenya, V. P. and Rusanov, I. B. and Ryskin, A. Ya.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {7},
    issue = {10},
    pages = {382},
    year = {1968},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_25794.shtml},
}