1. The average size of nonsingular sets in a graph, in Finite and Infinite Combinatorics in Sets and Logic;Imrich,1993
2. Graph generated union-closed families of sets;Knill,1993
3. A note on the union-closed sets conjecture;Lo Faro;J. Austr. Math. Soc. Ser. A,1994
4. Union-closed sets conjecture: improved bounds;Lo Faro;J. Combin. Math. Combin. Comput.,1994
5. A note of the union-closed sets conjecture;Norton;J. Austr. Math. Soc. Ser. A,1993