József Balogh Dhruv Mubayi A new short proof of a theorem of Ahlswede and Khachatrian. 326-330 2008 115 J. Comb. Theory, Ser. A 2 http://dx.doi.org/10.1016/j.jcta.2007.03.010 db/journals/jct/jcta115.html#BaloghM08