@article{PismaZhETF.54.291,
    title = {The effective mass of a quantum polaron},
    author = {Gogolin, A. O. and Ioselevich, A. S.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {54},
    issue = {5},
    pages = {291},
    year = {1991},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_18883.shtml},
}