@article{PismaZhETF.31.342,
    title = {Double phase transition},
    author = {Sannikov, D. G.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {31},
    issue = {6},
    pages = {342},
    year = {1980},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_20308.shtml},
}