@article{PismaZhETF.49.343,
    title = {Gapless fermion excitations at vortices in superfluids and superconductors},
    author = {Volovik, G. E.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {49},
    issue = {6},
    pages = {343},
    year = {1989},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_16919.shtml},
}