@article{PismaZhETF.52.959,
    title = {Stimulated emission on transitions between excited states and ground state of an acceptor impurity in germanium},
    author = {Murav'ev, A. V. and Pavlov, S. G. and Pastin, V. N.},
    journal = {Письма в ЖЭТФ},
    volume = {52},
    issue = {6},
    pages = {959},
    year = {1990},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_17509.shtml},
}