@article{ELA_2009__18__a10,
     author = {Djokovi\'c, Dragomir \v{Z}. and Severini, Simone and Sz\"oll\H{o}si, Ferenc},
     title = {Rational orthogonal versus real orthogonal},
     journal = {The electronic journal of linear algebra},
     pages = {649--673},
     publisher = {mathdoc},
     volume = {18},
     year = {2009},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/ELA_2009__18__a10/}
}