
REFERENCES

Bellamy, O. S.; Cadogan, C. C. Subsets of positive integers: their cardinality and maximality properties. Proceedings of the Tenth Southeastern Conference on Combinatorics, Graph Theory and Computing (Florida Atlantic Univ., Boca Raton, Fla., 1979), pp. 167178, Congress. Numer., XXIIIXXIV, Utilitas Math., Winnipeg, Man., 1979. MR0561043 (82b:10006)
