@article{PismaZhETF.14.523,
    title = {Constancy of Total Cross Sections and the Process $\pi^-p \to \eta$ n},
    author = {Babaev, Z. R.},
    journal = {Письма в ЖЭТФ},
    volume = {14},
    issue = {9},
    pages = {523},
    year = {1971},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_24952.shtml},
}