@article{PismaZhETF.43.570,
    title = {Laser resonant photoionization detection of traces of the radioactive isotope $^{221}Fr$ in a sample},
    author = {Andreev, S. V. and Letokhov, V. S. and Mishin, V. I.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {43},
    issue = {12},
    pages = {570},
    year = {1986},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_21506.shtml},
}