@article{ADM_2004_1_a2,
     author = {Vitalij M. Bondarenko and Andrej M. Polishchuk},
     title = {Minimax sums of posets and the quadratic {Tits} form},
     journal = {Algebra and discrete mathematics},
     pages = {17--36},
     year = {2004},
     number = {1},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/ADM_2004_1_a2/}
}