@article{PismaZhETF.15.577,
    title = {Theory of Bound States of Phonons with Impurity Centers and Excitons},
    author = {Rashba, E. I.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {15},
    issue = {9},
    pages = {577},
    year = {1972},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_26663.shtml},
}