@article{PismaZhETF.15.461,
    title = {Quantum Frequency Reference at 3.39 $\mu$ Wavelength},
    author = {Koshelyavskii, N. B. and Tatarenkov, V. M. and Titov, A. N.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {15},
    issue = {8},
    pages = {461},
    year = {1972},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_26624.shtml},
}