@article{PismaZhETF.18.443,
    title = {Pion condensation in neutron stars},
    author = {Migdal, A. B.},
    journal = {Письма в ЖЭТФ},
    volume = {18},
    issue = {7},
    pages = {443},
    year = {1973},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_24015.shtml},
}