Venn Diagrams and Symmetric Chain Decompositions in the Boolean Lattice.

Jerrold R. Griggs Charles E. Killian Carla D. Savage Venn Diagrams and Symmetric Chain Decompositions in the Boolean Lattice. 2004 11 Electr. J. Comb. 1 http://www.combinatorics.org/Volume_11/Abstracts/v11i1r2.html db/journals/combinatorics/combinatorics11.html#GriggsKS04