@article{PismaZhETF.33.357,
    title = {Infinite set of conservation laws for a relativistic string},
    author = {Isaev, A. P.},
    journal = {Письма в ЖЭТФ},
    volume = {33},
    issue = {7},
    pages = {357},
    year = {1981},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_23028.shtml},
}