@article{PismaZhETF.27.612,
    title = {Singularities of the energy "gap" of a superconductor},
    author = {Makarov, V. I.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {27},
    issue = {11},
    pages = {612},
    year = {1978},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_23784.shtml},
}