@article{PismaZhETF.23.264,
    title = {Heisenberg model in a magnetic field, and metamagnetism of Jahn-Teller systems},
    author = {Kugel', K. I. and Khomskii, B. I.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {23},
    issue = {5},
    pages = {264},
    year = {1976},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_27478.shtml},
}