@article{PismaZhETF.50.408,
    title = {Variation in nuclear composition of primary cosmic rays in the energy range $10^{17}-10^{19}$ eV},
    author = {D'yakonov, M. N. and Egorova, V. P. and Ivanov, A. A. and Knurenko, S. P. and Kolosov, V. A. and Nikol'skii, S. I. and Pavlov, V. N. and Sleptsov, I. E.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {50},
    issue = {10},
    pages = {408},
    year = {1989},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_17143.shtml},
}