@article{PismaZhETF.51.440,
    title = {Effective gauge theory of strongly correlated systems},
    author = {Karchev, N. I.},
    journal = {Письма в ЖЭТФ},
    volume = {51},
    issue = {9},
    pages = {440},
    year = {1990},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_17296.shtml},
}