@article{PismaZhETF.91.578,
    title = {Spontaneous breaking of four-fold rotational symmetry in two-dimensional electronic systems explained as a continuous topological transition},
    author = {Zverev, M. V. and Clark, J. W. and Nussinov, Z. and Khodel, V. A.},
    journal = {Письма в ЖЭТФ},
    volume = {91},
    issue = {10},
    pages = {578},
    year = {2010},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_28826.shtml},
}