Penny E. Haxell Tomasz Luczak Yuejian Peng Vojtech Rödl Andrzej Rucinski Miklós Simonovits Jozef Skokan 67-83 2006 113 J. Comb. Theory, Ser. A 1 http://dx.doi.org/10.1016/j.jcta.2005.02.005 db/journals/jct/jcta113.html#HaxelllPRRSS06